History of the United States
A hundred English colonists on a swampy island, a constitution argued out over one Philadelphia summer, a country that doubled its size for four cents an acre and fought a civil war over who counted as free, and the superpower that came out the other side
The United States began as a scattering of English colonies clinging to the Atlantic coast, built on land taken from Native nations and, from 1619, on the labor of enslaved Africans. In two centuries it declared independence, argued a federal constitution into existence, expanded to the Pacific, and nearly tore itself apart over slavery. Reconstruction promised equal citizenship and then abandoned it to Jim Crow. Industrialization, mass immigration, two world wars, and a Great Depression remade the country into a global power, and the second half of the twentieth century brought the Cold War, the civil rights movement, the Moon landing, Vietnam, and the wars that followed September 11. This is the national spine, with doorways to the fuller stories of the Revolution, the Civil War, the slave trade, the world wars, the Cold War, civil rights, and spaceflight.
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- May 1607Well documented
Primary source · 2 sourceswhy?
Best source: A Short History of Jamestown
Cited as a "primary" source (no stronger domain match).Jamestown Becomes the First Permanent English Colony
Roughly 100 colonists left England in late December 1606 on three ships, the Susan Constant, the Godspeed, and the Discovery, funded by a joint-stock venture called the Virginia Company. They reached Chesapeake Bay the following April and on May 13, 1607, landed on a narrow peninsula in the James River. The settlement they built there, named Jamestown after King James I, became the first permanent English settlement in North America. England had tried before and failed, most famously at the lost colony of Roanoke in 1587. The early Jamestown years were brutal: disease, starvation, and conflict with the Powhatan people killed most of the first arrivals, and the colony survived largely on the tobacco trade that took hold in the following decade.
Why it matters: Jamestown is where permanent English-speaking settlement of what became the United States begins. Its survival established the pattern of colonization by chartered companies chasing profit, tied the Chesapeake economy to tobacco, and set the stage for both large-scale land-taking from Native nations and, within twelve years, the arrival of the first enslaved Africans. Everything in the later national story runs downstream from this foothold on the James River.
How we know: Jamestown's founding is documented in the Virginia Company's own records and colonists' accounts, and the original 1607 fort site was rediscovered and excavated by archaeologists beginning in 1994, confirming the settlement's location and early structures.
Landing date: May 13-14, 1607 · Sponsor: The Virginia Company of London · Colonists: Roughly 100-104, on three ships · Significance: First permanent English settlement in North America
Sources - August 1619Well documented
Primary source · 2 sourceswhy?
Best source: 400 Years of African American History
Cited as a "primary" source (no stronger domain match).The First Enslaved Africans Arrive at Point Comfort
In late August 1619, an English privateer ship called the White Lion, sailing under Dutch authority, reached Point Comfort in Virginia carrying Africans it had seized from a Spanish slave ship. The colonists recorded the arrival of what they called "20 and odd" Africans, purchased by the colony's governor and merchant in exchange for provisions. These men and women, taken from west central Africa, were among the first Africans in English-occupied North America. Point Comfort is now part of Fort Monroe National Monument in Hampton, Virginia. Their arrival did not create slavery overnight as a fully formed legal system, but it marked the beginning of a practice that Virginia and other colonies would harden into hereditary racial slavery over the following decades.
Why it matters: This is the documented beginning of African slavery in the territory that became the United States, a system that would grow to hold four million people by 1861 and stand at the center of the nation's deepest conflict. The 1619 landing has become a reference point for how far back slavery reaches in American history, predating the Mayflower and nearly every other founding story by a year.
How we know: The arrival is recorded in a 1619 letter by the colonist John Rolfe describing the "20 and odd" Africans, and modern historians have traced the White Lion's voyage and the captives' origins through Spanish, English, and Virginia colonial records.
Date: Late August 1619 (now dated to about August 25) · Ship: The White Lion, an English privateer under Dutch authority · Number: "20 and odd" Africans · Place: Point Comfort, Virginia (now Fort Monroe National Monument)
SourcesRelated timelines- The Atlantic Slave Trade → · The White Lion's captives were seized from a Spanish slaver crossing the Middle Passage; see the Atlantic Slave Trade timeline for the wider forced migration of enslaved Africans.
- November 1620Well documented
Reputable source · 2 sourceswhy?
Best source: Mayflower Compact
The domain "history.com" is on our Reputable source registry.The Pilgrims Sign the Mayflower Compact
In November 1620 a ship called the Mayflower carried English religious separatists, later called the Pilgrims, along with other passengers, toward a landing in northern Virginia. Storms pushed them far off course to Cape Cod, outside the territory their patent covered. To hold the group together in a place where their legal authority did not reach, 41 adult male passengers signed a short agreement, the Mayflower Compact, in which they covenanted to combine themselves into a civil body politic and to make and obey just and equal laws for the good of the colony. They went on to found Plymouth Colony. The original document is lost; its wording survives through the writings of the Plymouth leader William Bradford, and Pilgrim Hall Museum holds an early printing.
Why it matters: The Mayflower Compact is often treated as the first written framework of self-government in what became the United States, a small group agreeing to govern itself by consent rather than by a distant authority. It carried real weight in shaping later American ideas that legitimate government rests on the agreement of the governed, a thread that runs through the Declaration of Independence and the Constitution.
How we know: The text of the Compact and the account of the 1620 voyage come from William Bradford's manuscript history Of Plymouth Plantation and from the 1622 account known as Mourt's Relation, both first-hand Pilgrim sources.
Signed: November 1620, aboard the Mayflower off Cape Cod · Signers: 41 adult male colonists · Colony founded: Plymouth · Significance: Early written framework of colonial self-government
Sources- HISTORY. Mayflower Compact · reference
- Pilgrim Hall Museum. The Mayflower Compact · reference
- 1763Well documented
Reputable source · 2 sourceswhy?
Best source: French and Indian War / Seven Years' War, 1754-63
The domain "history.state.gov" is on our Reputable source registry.The French and Indian War Ends and Britain Taxes the Colonies
The French and Indian War, the North American front of the wider Seven Years' War, ran from 1754 to 1763 and pitted Britain and its colonists against France and its Native allies. It ended with the Treaty of Paris in February 1763, by which Britain took Canada from France and Florida from Spain, becoming the dominant European power in eastern North America. Winning had been enormously expensive, roughly doubling the British national debt, and London decided the colonies should help pay for their own defense. Starting with the Sugar Act of 1764 and the Stamp Act of 1765, Parliament imposed a series of taxes on the colonies. Colonists who had no representation in Parliament objected sharply, and the dispute over taxation and authority hardened over the next decade into the crisis of independence.
Why it matters: The war's end reset the relationship between Britain and its colonies. Victory removed the French threat that had made colonists value British protection, while the debt drove the taxes that colonists came to see as tyranny. The slogan "no taxation without representation" grew directly out of this moment, making 1763 the hinge between colonial loyalty and the road to revolution.
How we know: The war's conclusion and the tax laws that followed are documented in the Treaty of Paris of 1763, the texts of the Sugar Act and Stamp Act, and extensive British parliamentary and colonial records of the period.
War years: 1754-1763 · Ended by: Treaty of Paris, February 1763 · British gains: Canada from France, Florida from Spain · First new taxes: Sugar Act (1764), Stamp Act (1765)
SourcesRelated timelines- The American Revolution → · The taxes imposed after 1763 set off the resistance that became the American Revolution; see that timeline for the Stamp Act crisis, the Boston Tea Party, and the war itself.
- July 4, 1776Well documented
Primary source · 2 sourceswhy?
Best source: Declaration of Independence (1776)
Cited as a "primary" source (no stronger domain match).The Colonies Declare Independence
After a decade of escalating disputes over taxation and authority, and more than a year of open fighting, the Second Continental Congress voted for independence and, on July 4, 1776, adopted the Declaration of Independence. The text was drafted largely by Thomas Jefferson, then revised by a committee and by Congress. It set out a philosophy of government resting on the idea that all men are created equal and hold unalienable rights, listed grievances against King George III, and declared that the thirteen united colonies were, and of right ought to be, free and independent states, absolved of allegiance to the British Crown. The Revolutionary War would grind on until 1783, but the political break with Britain was now formal and public.
Why it matters: The Declaration is the founding statement of the United States as a nation and the source of its most quoted lines about equality and rights, principles that later Americans, from abolitionists to the civil rights movement, would hold the country to. The gap between its promise that all men are created equal and the reality of slavery and exclusion has driven American reform arguments ever since.
How we know: The signed Declaration of Independence survives in the National Archives, and the drafting process is documented in the records of the Continental Congress and in Jefferson's own later recollections.
Adopted: July 4, 1776 · Principal author: Thomas Jefferson · Body: The Second Continental Congress · Core claim: The colonies are free and independent states
SourcesRelated timelines- The American Revolution → · The Declaration came in the middle of the Revolutionary War; see the American Revolution timeline for the causes, battles, and 1783 peace that won the independence it announced.
- 1787Well documented
Primary source · 2 sourceswhy?
Best source: A More Perfect Union: The Creation of the U.S. Constitution
Cited as a "primary" source (no stronger domain match).The Constitutional Convention Frames a New Government
Under the Articles of Confederation, the first national government of the independent states, the central government was too weak to regulate commerce, raise reliable revenue, or hold the union together. In the summer of 1787, delegates gathered at the Pennsylvania State House in Philadelphia to fix it. Seventy-four delegates were appointed and 55 attended, with George Washington presiding and James Madison among the driving forces. Rather than amend the Articles, they wrote an entirely new Constitution, creating a stronger federal government with three branches and a system of checks and balances, and compromising bitterly over representation and over slavery. They signed the finished document on September 17, 1787, and sent it to the states. Nine states had to ratify it for it to take effect, which they did by 1788, and the new government began in 1789.
Why it matters: The Constitution is the framework the United States still governs itself by, the oldest written national constitution in continuous use. The compromises made in that Philadelphia room, including the ones that protected slavery and counted enslaved people as three-fifths of a person for representation, shaped American politics for generations and left conflicts that would eventually be settled only by civil war.
How we know: The Constitution itself survives with its 39 signatures, and the convention's debates are known from Madison's detailed notes and from the ratification records of the individual states.
Convention: Philadelphia, May to September 1787 · Delegates attending: 55 of 74 appointed · Signed: September 17, 1787 · In effect: 1789, after ratification by the states
- December 15, 1791Well documented
Primary source · 2 sourceswhy?
Best source: Bill of Rights (1791)
Cited as a "primary" source (no stronger domain match).The Bill of Rights Is Ratified
Several states had ratified the Constitution only on the understanding that a list of protected rights would be added, and many people feared the new federal government could trample individual liberties. In 1789 Congress proposed a set of amendments, and on December 15, 1791, three-quarters of the states ratified ten of them, known ever since as the Bill of Rights. They guarantee freedoms including speech, religion, press, and assembly, protection against unreasonable searches, the right to a fair trial, and limits on federal power, defining citizens' rights in relation to the newly established government. The framers of these protections had fresh memories of British violations of civil rights before and during the Revolution.
Why it matters: The Bill of Rights sits at the heart of American ideas about individual liberty and limited government. Its guarantees, especially the First Amendment's protections of speech and religion and the later-incorporated protections applied to the states, have been argued over in courtrooms for more than two centuries and remain central to how Americans understand their freedoms.
How we know: The ratified amendments and the congressional resolution proposing them survive in the National Archives, and the state ratification votes that completed the process by December 1791 are documented in the legislative records of the period.
Ratified: December 15, 1791 · Number of amendments: First 10 amendments to the Constitution · Protects: Speech, religion, press, assembly, fair trial, and more · Proposed by Congress: 1789
Sources- National Archives. Bill of Rights (1791) · primary
- HISTORY. Bill of Rights · reference
- 1803Well documented
Primary source · 2 sourceswhy?
Best source: Louisiana Purchase Treaty (1803)
Cited as a "primary" source (no stronger domain match).The Louisiana Purchase Doubles the Country
President Thomas Jefferson sent negotiators to France hoping to buy the port of New Orleans and secure access to the Mississippi River. Napoleon, having given up his plans for a French empire in North America, instead offered the entire Louisiana Territory. In 1803 the United States purchased 828,000 square miles of land west of the Mississippi for $15 million, roughly four cents an acre, doubling the size of the country in a single treaty. Jefferson, normally a strict reader of the Constitution, privately doubted whether the federal government had the power to acquire new territory, but the chance to expand across the continent outweighed his misgivings. The purchase opened the way for the Lewis and Clark expedition and for decades of westward settlement.
Why it matters: The Louisiana Purchase set the United States on the path to becoming a continental power and made westward expansion the defining project of the nineteenth century. It also sharpened the coming crisis over slavery, because every new territory carved from this land raised the question of whether it would be free or slave, a question that ran straight toward the Civil War.
How we know: The Louisiana Purchase Treaty and its terms survive in the National Archives, and the negotiation is documented in the correspondence of Jefferson and his envoys Robert Livingston and James Monroe.
Year: 1803 · Sold by: France, under Napoleon · Price: $15 million for 828,000 square miles · Effect: Roughly doubled the size of the United States
- 1820Well documented
Primary source · 2 sourceswhy?
Best source: Missouri Compromise (1820)
Cited as a "primary" source (no stronger domain match).The Missouri Compromise Draws a Line Through Slavery
As settlers pushed west into the land bought in the Louisiana Purchase, the question of whether new states would allow slavery threatened to break the union apart. Missouri applied to join as a slave state in 1819, which would have tipped the even balance of free and slave states in the Senate. Congress found a temporary answer in the Missouri Compromise, passed in March 1820: Missouri entered as a slave state and Maine as a free state at the same time, keeping the balance, and slavery was prohibited in the rest of the Louisiana Territory north of the line of 36 degrees 30 minutes latitude. It settled the immediate crisis but drew a literal line dividing the country into competing halves, half free and half slave.
Why it matters: The Missouri Compromise revealed that slavery was the fault line running through American expansion, and that each new state would reopen the wound. The 36 degrees 30 minutes line held for a generation before the Kansas-Nebraska Act and the Dred Scott decision tore it up, and the failure of these compromises to hold pushed the country toward civil war.
How we know: The compromise legislation and its 36 degrees 30 minutes provision survive in the statutes passed by Congress in 1820, preserved in the National Archives and the records of the U.S. Senate.
Passed: March 1820 · Balance struck: Missouri (slave) and Maine (free) admitted together · The line: Slavery barred north of 36 degrees 30 minutes latitude · Status: A temporary settlement of a recurring crisis
Sources - 1830 (removals through 1839)Well documented
Primary source · 2 sourceswhy?
Best source: President Andrew Jackson's Message to Congress on Indian Removal (1830)
Cited as a "primary" source (no stronger domain match).The Indian Removal Act and the Trail of Tears
In 1830 President Andrew Jackson signed the Indian Removal Act, which authorized the federal government to negotiate treaties to remove Native American tribes living east of the Mississippi River, chiefly in Georgia, Tennessee, Alabama, Mississippi, and North Carolina, and relocate them to land in the West. The Cherokee resisted in the courts and won a Supreme Court ruling, but Jackson's administration pressed removal anyway. In May 1838, U.S. Army troops and state militia forcibly evicted more than 16,000 Cherokee from their homelands and drove them west on what became known as the Trail of Tears. More than a thousand Cherokee died on the journey, and an unknown number, perhaps several thousand, perished from the consequences of the forced migration. The relocation was completed by the end of March 1839.
Why it matters: The Indian Removal Act and the Trail of Tears are among the clearest cases of the United States using federal power to dispossess and destroy Native nations for the benefit of white settlement. The episode is a documented atrocity, not a matter of dispute, and it stands as a permanent counterweight to any telling of American expansion as simply the spread of freedom across open land.
How we know: The Indian Removal Act and the treaties made under it are federal records, and the Cherokee removal is documented in Army records, missionary accounts, and Cherokee sources, which support the death toll of more than a thousand on the march and thousands more from its effects.
Act signed: 1830, by President Andrew Jackson · Cherokee removed: More than 16,000 · Deaths on and from the march: More than a thousand, perhaps several thousand · Removal completed: March 1839
- 1846-1848Well documented
Primary source · 2 sourceswhy?
Best source: Treaty of Guadalupe Hidalgo (1848)
Cited as a "primary" source (no stronger domain match).Manifest Destiny and the Mexican-American War
In the 1840s many Americans embraced the ideology of manifest destiny, the belief that the United States was destined to extend its nation across the continent. Acting on that impulse, and after the annexation of Texas, the United States in 1845 embarked on what the State Department's own history calls its first offensive war by invading Mexico. The Mexican-American War ended with the Treaty of Guadalupe Hidalgo, signed on February 2, 1848, by which Mexico ceded 55 percent of its territory, including present-day California, Nevada, and Utah and parts of Arizona, New Mexico, Colorado, and other states. The United States paid Mexico $15 million and extended its boundaries west to the Pacific Ocean.
Why it matters: The war gave the United States its Pacific coastline and the Southwest, completing the continental expansion begun with Louisiana, and the discovery of gold in newly acquired California the same year drew hundreds of thousands west. It also handed the country an enormous new territory whose status, free or slave, reignited the sectional crisis and helped set the stage for the Civil War.
How we know: The Treaty of Guadalupe Hidalgo survives in the National Archives with its terms of cession and payment, and the war and the ideology of manifest destiny are documented across U.S. and Mexican government records of the 1840s.
War years: 1846-1848 · Ended by: Treaty of Guadalupe Hidalgo, February 2, 1848 · Territory ceded: 55 percent of Mexico's territory · Payment: $15 million
- 1850Well documented
Primary source · 2 sourceswhy?
Best source: Chapter 1: Race, Slavery, and Freedom
Cited as a "primary" source (no stronger domain match).Slavery, Cotton, and the Compromise of 1850
By the mid-nineteenth century slavery had become the foundation of the Southern economy. The 1793 cotton gin caused a boom in cotton production that rapidly expanded slavery beyond the Appalachians, and by the eve of the Civil War four million men, women, and children lived under chattel slavery in the United States. Between 1820 and 1860 the domestic slave trade tore roughly a million enslaved people from their families and forced them into the Deep South. In 1850, as the land won from Mexico reopened the question of slavery's expansion, Senator Henry Clay engineered the Compromise of 1850, a package of five statutes: California entered as a free state, the slave trade ended in Washington, D.C., territorial governments were set up for Utah and New Mexico, and, as the South's price, a far harsher Fugitive Slave Act required officials and citizens in every state to help capture people escaping bondage.
Why it matters: The Compromise of 1850 was the last time a grand bargain held the union together over slavery. The Fugitive Slave Act enraged the North by forcing free states to participate in slavery's enforcement, fueling abolitionism and works like Uncle Tom's Cabin, while the underlying dispute only deepened. Within a decade the compromises had collapsed and the country was at war.
How we know: The five statutes of the Compromise of 1850 are preserved in the records of Congress, and the scale of slavery and the domestic slave trade is documented in federal census returns, slave manifests, and the extensive scholarship built on them.
Enslaved population by 1860: About four million people · Domestic slave trade, 1820-1860: Roughly a million people sold south · Compromise of 1850: Five statutes, engineered by Henry Clay · The South's price: A stronger Fugitive Slave Act
SourcesRelated timelines- The Atlantic Slave Trade → · American slavery grew out of the Atlantic slave trade that carried millions of Africans across the Middle Passage; see that timeline for the origins of the system.
- 1860-1861Well documented
Primary source · 2 sourceswhy?
Best source: Telegram Announcing the Surrender of Fort Sumter (1861)
Cited as a "primary" source (no stronger domain match).Secession and the Attack on Fort Sumter
Abraham Lincoln's election in November 1860, on a platform opposing the spread of slavery, convinced much of the South that its future in the Union was over. South Carolina became the first state to secede on December 20, 1860, and six more Deep South states followed, forming the Confederate States of America in February 1861. The crisis broke into war at Fort Sumter, a federal fort in Charleston Harbor. Confederate forces demanded its surrender, and the first engagement of the Civil War took place there on April 12 and 13, 1861. Major Robert Anderson defended the fort for 34 hours until the quarters were entirely burned, then accepted terms of evacuation and marched out. No one was killed in the bombardment, but the war it began would kill more Americans than any other in the nation's history.
Why it matters: Fort Sumter turned the long argument over slavery and union into open war. The choice of secession by eleven states eventually, and the decision of Lincoln's government to fight to preserve the Union, set the terms of a four-year conflict that would end slavery and remake the country. This event is the doorway into that war.
How we know: Secession ordinances survive as state records, and the Fort Sumter engagement is documented in official military correspondence, including Major Anderson's own telegram announcing the surrender, held in the National Archives.
First state to secede: South Carolina, December 20, 1860 · Confederacy formed: February 1861 · War began: Fort Sumter, April 12-13, 1861 · Trigger: Lincoln's 1860 election
SourcesRelated timelines- The American Civil War → · This is the outbreak of the Civil War; see the American Civil War timeline for the campaigns, battles, and the war's course from 1861 to 1865.
- January 1, 1863Well documented
Primary source · 2 sourceswhy?
Best source: Emancipation Proclamation (1863)
Cited as a "primary" source (no stronger domain match).The Emancipation Proclamation
On January 1, 1863, in the middle of the Civil War, President Lincoln signed the Emancipation Proclamation, declaring that all persons held as slaves within the rebelling states were, and henceforward should be, free. The proclamation was a war measure grounded in the president's authority as commander in chief, and its reach was limited: it applied only to the Confederate states in rebellion and left slavery untouched in the loyal border states of Maryland, Kentucky, and Missouri, where the government had no wartime justification to act. Freedom for those it named depended on Union armies actually reaching them. The proclamation also opened the way for Black men to serve in the Union forces, and nearly 200,000 did.
Why it matters: The Emancipation Proclamation changed the purpose of the war, making the destruction of slavery an explicit Union aim alongside preserving the country. It did not free everyone, and full legal abolition would wait for the Thirteenth Amendment, but it committed the United States to ending slavery and drew hundreds of thousands of Black soldiers into the fight for their own freedom.
How we know: The signed proclamation survives in the National Archives, and its scope, limitations, and border-state exclusions are documented in the text itself and in Lincoln's contemporaneous statements about signing it.
Signed: January 1, 1863 · Scope: Enslaved people in the rebelling Confederate states · Excluded: The loyal border states, where slavery continued · Black troops enabled: Nearly 200,000 served the Union
SourcesRelated timelines- The American Civil War → · See the American Civil War timeline for the military campaigns of 1863 and how Union victory turned the proclamation's promise into reality on the ground.
- April 1865Well documented
Primary source · 3 sourceswhy?
Best source: Articles of Agreement Relating to the Surrender of the Army of Northern Virginia (1865)
Cited as a "primary" source (no stronger domain match).Appomattox and the Assassination of Lincoln
On April 9, 1865, Generals Ulysses S. Grant and Robert E. Lee met in the parlor of a house at Appomattox Court House, Virginia, to arrange the surrender of the Army of Northern Virginia, which effectively ended the Civil War. Grant's terms were generous: Lee's men could go home if they laid down their arms and pledged to stop fighting. The most important symbol of the Confederacy was gone. Five days later, on April 14, 1865, at about 10:20 p.m., the actor John Wilkes Booth crept up behind President Lincoln at Ford's Theater and shot him in the back of the head. Lincoln was carried to a house across the street and died the following morning at 7:22 a.m., the first American president to be assassinated.
Why it matters: Lee's surrender ended four years of war that killed more Americans than any other conflict and destroyed slavery. Lincoln's murder days later removed the leader who had preserved the Union and set the terms of emancipation, at the very moment the country faced the harder task of rebuilding the South and defining freedom for four million formerly enslaved people. His death shadowed the entire Reconstruction that followed.
How we know: The surrender terms survive as a signed document in the National Archives, and the assassination is documented in eyewitness testimony, the trial of Booth's conspirators, and the medical record of Lincoln's death, all preserved in the National Archives.
Lee's surrender: April 9, 1865, at Appomattox Court House · Union commander: General Ulysses S. Grant · Lincoln shot: April 14, 1865, by John Wilkes Booth · Lincoln died: April 15, 1865, at 7:22 a.m.
SourcesRelated timelines- The American Civil War → · See the American Civil War timeline for the final 1865 campaigns that forced Lee's surrender and the war's last months.
- 1865-1870Well documented
Primary source · 2 sourceswhy?
Best source: 13th Amendment to the U.S. Constitution: Abolition of Slavery (1865)
Cited as a "primary" source (no stronger domain match).The Reconstruction Amendments Rewrite Freedom
In the five years after the Civil War, the Constitution was amended three times to remake the legal status of Black Americans. The Thirteenth Amendment, ratified December 6, 1865, abolished slavery, declaring that neither slavery nor involuntary servitude, except as punishment for crime, shall exist within the United States. The Fourteenth Amendment, ratified July 9, 1868, made all persons born or naturalized in the United States citizens and guaranteed them the equal protection of the laws, overturning the Dred Scott decision that had denied Black people citizenship. The Fifteenth Amendment, ratified in 1870, barred denying the vote on account of race, color, or previous condition of servitude. Together these are known as the Reconstruction Amendments.
Why it matters: The Reconstruction Amendments are the constitutional foundation of civil rights in the United States, the legal basis on which nearly every later expansion of equality has been argued. The Fourteenth Amendment's equal protection and citizenship clauses in particular became the tool used to challenge segregation and win the great civil rights cases of the twentieth century. The promise they wrote into the Constitution, though, would be gutted in practice within a decade.
How we know: The three amendments and their ratification dates are recorded in the National Archives and the constitutional record, and their texts are the operative law of the United States.
13th Amendment: 1865, abolished slavery · 14th Amendment: 1868, citizenship and equal protection · 15th Amendment: 1870, voting rights regardless of race · Collective name: The Reconstruction Amendments
- 1877Well documented
Reputable source · 2 sourceswhy?
Best source: About the Reconstruction Era
The domain "home.nps.gov" is on our Reputable source registry.Reconstruction Ends and Jim Crow Rises
For a little over a decade after the Civil War, federal power in the South protected the new rights of Black citizens, and Black men voted and held office. It ended in a political bargain. The controversial presidential election of Rutherford B. Hayes in 1876 was resolved through an agreement to remove the remaining U.S. Army units from the former Confederate states. With federal troops gone, Southern states were free to enact discriminatory laws that stripped Black Americans of their civil and voting rights. The result was the re-establishment of Black Codes and the rise of Jim Crow laws, a system of racial segregation and disenfranchisement that used poll taxes, literacy tests, and terror to keep Black Americans from voting booths and to enforce separation of the races.
Why it matters: The end of Reconstruction is one of the great reversals in American history: rights guaranteed by the Constitution in 1868 and 1870 were nullified in practice by 1877, and it took the civil rights movement of the mid-twentieth century, nearly ninety years later, to begin restoring them. Jim Crow shaped the lives of generations of Black Southerners and the geography of American race relations well into living memory.
How we know: The 1877 troop withdrawal and the subsequent spread of segregation and disenfranchisement laws are documented in federal and state records and in the National Park Service's history of the Reconstruction era.
Trigger: The disputed 1876 election of Rutherford B. Hayes · Key act: Withdrawal of U.S. Army troops from the South · Result: Black Codes and Jim Crow segregation laws · Duration: Enforced into the mid-20th century
SourcesRelated timelines- The Civil Rights Movement → · The Jim Crow system that Reconstruction's collapse produced is what the civil rights movement fought to dismantle; see that timeline for the long struggle against it.
- c. 1869-1914Well documented
Reputable source · 3 sourceswhy?
Best source: Ellis Island: History & Culture
The domain "nps.gov" is on our Reputable source registry.Railroads, Industry, and Mass Immigration
In the decades after the Civil War the United States industrialized at extraordinary speed. The first transcontinental railroad opened to traffic on May 10, 1869, when the Central Pacific and Union Pacific lines met at Promontory Summit, Utah, cutting coast-to-coast travel from months to days. The Central Pacific had recruited over 11,000 workers from China to build its western half. Steel, oil, and manufacturing fortunes grew alongside the rail network, and the labor came in large part from immigrants. From 1892 to 1924, Ellis Island in New York Harbor was the country's largest and most active immigration station, processing over 12 million immigrants, with 1907 its single busiest year. Most came from southern and eastern Europe, transforming American cities.
Why it matters: This is the era when the United States became an industrial power and a nation of immigrants on a mass scale. The railroads knit the continent into a single market and accelerated the settlement that displaced remaining Native nations, while the waves of new arrivals through Ellis Island reshaped the country's population, cities, and politics. The wealth and inequality of what Mark Twain called the Gilded Age set the stage for the reform movements that followed.
How we know: The transcontinental railroad's completion is documented in the records of the two railroad companies and the Golden Spike ceremony, and Ellis Island's immigration figures come from the federal immigration station's own processing records preserved by the National Park Service.
Transcontinental railroad completed: May 10, 1869, at Promontory Summit, Utah · Chinese workers on the Central Pacific: Over 11,000 · Immigrants through Ellis Island: Over 12 million, 1892-1924 · Busiest year: 1907
- May 18, 1896Well documented
Primary source · 2 sourceswhy?
Best source: Plessy v. Ferguson (1896)
Cited as a "primary" source (no stronger domain match).Plessy v. Ferguson Blesses "Separate but Equal"
In 1890 Louisiana passed the Separate Car Act, requiring separate railroad seating for white and Black passengers. A New Orleans group organized a test case: Homer Plessy, who was seven-eighths white, deliberately sat in a whites-only car and was arrested on June 7, 1892. His challenge reached the Supreme Court, which on May 18, 1896, ruled against him. The Court held that laws requiring equal but separate accommodations for the two races were constitutional, establishing the doctrine of separate but equal. Only Justice John Marshall Harlan dissented, writing that our Constitution is color-blind, and neither knows nor tolerates classes among citizens. The ruling gave federal blessing to racial segregation and stood for nearly sixty years.
Why it matters: Plessy v. Ferguson made segregation constitutional and became the legal backbone of Jim Crow across the South, sanctioning separate schools, transit, and public facilities that were rarely equal. It stood as binding precedent until Brown v. Board of Education overturned it in 1954, and Harlan's lone dissent became one of the most admired minority opinions in American law.
How we know: The Court's majority opinion and Harlan's dissent are preserved in the official U.S. Reports (163 U.S. 537) and the National Archives, and the case's origins in the Louisiana Separate Car Act are documented in state records and the National Park Service history of Homer Plessy.
Decided: May 18, 1896 · Doctrine established: "Separate but equal" · Vote: 7 to 1, Justice Harlan dissenting · Overturned by: Brown v. Board of Education, 1954
Sources- National Archives. Plessy v. Ferguson (1896) · primary
- National Park Service. Homer Plessy · reference
Related timelines- The Civil Rights Movement → · The segregation Plessy legalized is what the civil rights movement set out to end; see that timeline for the campaign that culminated in Brown v. Board and the civil rights laws.
- c. 1901-1914Well documented
Reputable source · 2 sourceswhy?
Best source: The Pure Food and Drug Act
The domain "visitthecapitol.gov" is on our Reputable source registry.The Progressive Era and the Trust Busters
The concentration of wealth and corporate power in the Gilded Age produced a broad reform movement known as Progressivism. President Theodore Roosevelt made a signature of it by turning federal antitrust law against giant corporations. In 1901 he instructed his Justice Department to break up the Northern Securities Company, a railroad holding company, as an illegal combination acting in restraint of trade; the Supreme Court agreed in 1904, and Roosevelt earned a reputation as a trust buster. Progressive pressure also produced consumer protection: after Upton Sinclair's 1906 novel The Jungle exposed filthy conditions in meatpacking, public outrage pushed Congress to pass the Pure Food and Drug Act of 1906, which prohibited misbranded or adulterated food and drugs and laid the foundation for the Food and Drug Administration.
Why it matters: The Progressive Era built the beginnings of the modern regulatory state, the idea that the federal government should check corporate power and protect ordinary consumers and workers. Antitrust enforcement, food and drug safety, and later reforms like the income tax and direct election of senators grew out of this period and reshaped the relationship between government, business, and citizens.
How we know: The Northern Securities case is documented in Supreme Court records and the Theodore Roosevelt Center's archive, and the Pure Food and Drug Act's passage is documented in congressional records held by the U.S. Capitol Visitor Center.
Trust-busting case: Northern Securities, ordered broken up in 1901, decided 1904 · President: Theodore Roosevelt · Consumer law: Pure Food and Drug Act, 1906 · Spark: Upton Sinclair's novel The Jungle
- April 1917Well documented
Primary source · 2 sourceswhy?
Best source: President Wilson's Address to Congress Leading to a Declaration of War Against Germany (1917)
Cited as a "primary" source (no stronger domain match).The United States Enters World War I
The United States stayed out of World War I for its first two and a half years, and Woodrow Wilson won reelection in 1916 partly on having kept the country out. Two German actions changed that. Germany resumed unrestricted submarine warfare in early 1917, sinking merchant and passenger ships, and the intercepted Zimmermann Telegram revealed a German offer to help Mexico recover territory it had lost to the United States. On April 2, 1917, Wilson went before a joint session of Congress to ask for a declaration of war, arguing that the world must be made safe for democracy. Congress voted for war, and the declaration against Germany was final on April 6, 1917. American troops began reaching Europe in numbers in 1918.
Why it matters: Entry into World War I marked the United States stepping onto the world stage as a decisive military power, and the fresh American forces helped tip the balance toward Allied victory in 1918. Wilson's vision of a postwar order built on democracy and a League of Nations shaped, and then frustrated, American foreign policy, and the war's disappointments fed the isolationism of the 1920s and 1930s.
How we know: Wilson's war message survives in the National Archives, along with the congressional declaration of war, and the causes including submarine warfare and the Zimmermann Telegram are documented in State Department and diplomatic records.
War message: April 2, 1917, by Woodrow Wilson · War declared: April 6, 1917, against Germany · Triggers: Unrestricted submarine warfare, the Zimmermann Telegram · Wilson's aim: To "make the world safe for democracy"
SourcesRelated timelines- World War I → · This is the American entry into World War I; see the World War I timeline for the war's origins, the Western Front, and the 1918 armistice.
- August 1920Well documented
Primary source · 2 sourceswhy?
Best source: 19th Amendment to the U.S. Constitution: Women's Right to Vote (1920)
Cited as a "primary" source (no stronger domain match).Women Win the Vote With the 19th Amendment
The campaign for women's suffrage had run for more than seventy years, from the 1848 Seneca Falls convention through decades of state-by-state fights, marches, and civil disobedience. Congress passed the Nineteenth Amendment on June 4, 1919, and sent it to the states. Ratification came down to Tennessee, which on August 18, 1920, became the 36th state to ratify, meeting the three-quarters threshold. The amendment declared that the right to vote shall not be denied or abridged on account of sex, and it was certified into law on August 26, 1920. The victory was real but incomplete: many Black women, especially in the Jim Crow South, and Native American women, who were not even recognized as citizens until 1924, remained shut out of the polls.
Why it matters: The Nineteenth Amendment enfranchised roughly half the adult population and stands as one of the largest single expansions of democracy in American history. It also showed both the power and the limits of constitutional change: winning the legal right to vote did not, on its own, deliver it to women of color, whose full access would depend on the later voting rights struggle.
How we know: The amendment and its ratification are recorded in the National Archives, and the June 1919 congressional passage and August 1920 Tennessee ratification are documented in the legislative and state records.
Passed Congress: June 4, 1919 · Ratified: August 18, 1920 (Tennessee, the 36th state) · Guarantee: Vote not denied on account of sex · Still excluded in practice: Many Black and Native American women
- October 1929Well documented
Reputable source · 2 sourceswhy?
Best source: The American Home Front Before World War II
The domain "nps.gov" is on our Reputable source registry.The Stock Market Crash and the Great Depression
After a decade of booming markets in the 1920s, the U.S. stock market crashed in late October 1929, wiping out billions of dollars of Americans' wealth and investment in a matter of days. The crash did not cause the Great Depression by itself, but it triggered a spiral of bank failures, collapsing demand, and business closures that deepened into the worst economic crisis in the nation's history. By 1933, at the height of the Depression, 24.9 percent of the total work force, about 12,830,000 people, was unemployed, roughly one worker in four. Farm prices collapsed, thousands of banks failed, and families across the country lost homes, savings, and livelihoods.
Why it matters: The Great Depression reshaped American politics and government for a generation. Mass unemployment and suffering discredited the hands-off economic philosophy of the 1920s, brought Franklin Roosevelt to power, and led to the New Deal's expansion of federal responsibility for the economy and for citizens' welfare. Its memory shaped American attitudes toward banks, work, and government well into the postwar decades.
How we know: The crash and its economic aftermath are documented in market records, federal economic data, and the unemployment statistics compiled and published by government sources and the Franklin D. Roosevelt Presidential Library.
Crash: Late October 1929 · Peak unemployment: 24.9 percent, about 12.8 million people, in 1933 · Wider effects: Thousands of bank failures, collapsing farm prices · Political result: The election of Franklin Roosevelt and the New Deal
SourcesRelated timelines- The Great Depression → · The 1929 crash, bank failures, the Dust Bowl, and the New Deal in depth
- 1933-1939Well documented
Primary source · 2 sourceswhy?
Best source: Social Security Act (1935)
Cited as a "primary" source (no stronger domain match).The New Deal Remakes the Federal Government
Franklin D. Roosevelt took office in March 1933 amid the depths of the Depression and launched a torrent of programs known as the New Deal to provide relief, recovery, and reform. He established the Civilian Conservation Corps in 1933, which put single men aged 18 to 25 to work improving public lands, forests, and parks, paying $30 a month with most sent home to families. The Works Progress Administration employed millions on public projects. The centerpiece of the reform effort was the Social Security Act, which Roosevelt signed on August 14, 1935, creating a system of federal old-age benefits and support for the unemployed, the blind, and dependent children, funded by taxes on wages and payrolls.
Why it matters: The New Deal permanently enlarged the role of the federal government in American life, establishing that Washington bears responsibility for economic security and for the welfare of citizens who cannot support themselves. Social Security remains one of the largest and most durable government programs in the country, and the New Deal coalition reshaped American politics for decades. It set the pattern of an activist federal government that later generations would either extend or fight to roll back.
How we know: The Social Security Act and its stated purpose survive in the National Archives, and the New Deal programs are documented in extensive federal records, agency archives, and the physical works of the CCC and WPA still visible today.
President: Franklin D. Roosevelt, from March 1933 · Civilian Conservation Corps: Established 1933, men aged 18-25 · Social Security Act: Signed August 14, 1935 · Aim: Relief, recovery, and reform
Sources - December 7, 1941Well documented
Primary source · 2 sourceswhy?
Best source: Joint Address to Congress Leading to a Declaration of War Against Japan (1941)
Cited as a "primary" source (no stronger domain match).Pearl Harbor Brings the United States Into World War II
On the morning of Sunday, December 7, 1941, Japanese carrier aircraft launched a surprise attack on the U.S. Pacific Fleet at Pearl Harbor, Hawaii. In less than ninety minutes Japanese planes destroyed or damaged 19 U.S. warships and 300 aircraft and killed over 2,400 American servicemen, nearly half of them aboard the battleship USS Arizona, which sank after a bomb ignited its forward magazine. The next day, December 8, President Roosevelt addressed Congress, calling December 7 a date which will live in infamy and asking it to recognize that a state of war existed with Japan. Congress declared war almost unanimously, with a single dissenting vote. Days later Germany and Italy declared war on the United States, bringing the country fully into World War II.
Why it matters: Pearl Harbor ended the long American debate over whether to enter the war and united the country behind total mobilization. The United States became the decisive industrial and military power of the Allied coalition, and the war it now joined would transform the nation into a global superpower and reshape the postwar world.
How we know: Roosevelt's war message survives in the National Archives, and the attack's casualties and damage are documented in Navy records and the histories maintained by the National WWII Museum.
Attack: December 7, 1941, Pearl Harbor, Hawaii · American dead: Over 2,400 servicemen · FDR's speech: December 8, 1941, "a date which will live in infamy" · Result: U.S. entry into World War II
SourcesRelated timelines- World War II → · This is the American entry into World War II; see the World War II timeline for the wider war in Europe and the Pacific from 1939 to 1945.
- 1945Well documented
Primary source · 2 sourceswhy?
Best source: The Bombing of Hiroshima and Nagasaki
Cited as a "primary" source (no stronger domain match).Victory and the Atomic Bomb End World War II
By the spring of 1945 the Allies had ground down Nazi Germany from east and west, and Germany surrendered on May 7-8, 1945, marked as Victory in Europe Day. The war against Japan continued in the Pacific. In August the United States used a new weapon: American atomic bombings of Hiroshima and Nagasaki on August 6 and August 9, 1945, were the first uses of atomic bombs against humans, killing tens of thousands of people, obliterating the cities, and contributing to the end of the war. Japan announced its surrender days later, and the formal surrender aboard the USS Missouri in Tokyo Bay on September 2, 1945, ended World War II. The decision to use the bomb remains among the most argued-over choices in American history.
Why it matters: The end of World War II left the United States the strongest power on earth, its homeland untouched and its economy dominant, and the atomic bombings opened the nuclear age that would define the Cold War and the constant threat of world-ending war. The moral and strategic debate over dropping the bomb, whether it saved lives by avoiding an invasion or was an atrocity against civilians, has never been settled.
How we know: The German and Japanese surrenders are documented in the signed instruments of surrender and Allied military records, and the atomic bombings are documented by the National Archives, the National Park Service, and the physical and human record at Hiroshima and Nagasaki.
V-E Day: May 8, 1945 (German surrender) · Atomic bombs: Hiroshima August 6, Nagasaki August 9, 1945 · Japan's formal surrender: September 2, 1945, aboard USS Missouri · Contested question: The justification for using the atomic bomb
SourcesRelated timelines- World War II → · See the World War II timeline for the full course of the war in Europe and the Pacific that these events brought to an end.
- 1947-1949Well documented
Primary source · 3 sourceswhy?
Best source: Truman Doctrine (1947)
Cited as a "primary" source (no stronger domain match).The Cold War Begins
The wartime alliance between the United States and the Soviet Union collapsed almost as soon as the fighting stopped, replaced by a global rivalry between capitalist democracy and Soviet communism. The United States adopted a policy of containment, aiming to stop the spread of communism. In the Truman Doctrine of March 1947, President Truman declared that it must be the policy of the United States to support free peoples resisting subjugation, and won aid for Greece and Turkey. In 1948 he signed the Marshall Plan, under which Congress appropriated $13.3 billion to rebuild the shattered economies of Western Europe. In 1949 the United States joined eleven other nations to form NATO, a military alliance built on the promise that an attack on one member would be treated as an attack on all.
Why it matters: The Cold War organized American foreign policy, military spending, and much of its domestic politics for more than four decades. Containment, foreign aid, and permanent alliances marked a decisive break from the isolationism of the interwar years and committed the United States to a leading role in the world. The rivalry drove the arms race, the space race, and proxy wars from Korea to Vietnam.
How we know: The Truman Doctrine speech and the Marshall Plan legislation survive in the National Archives, and the founding of NATO is documented in the North Atlantic Treaty and the diplomatic record of 1949.
Truman Doctrine: March 1947, containment of communism · Marshall Plan: Signed 1948, $13.3 billion for European recovery · NATO founded: 1949, collective defense alliance · Rival: The Soviet Union
SourcesRelated timelines- The Cold War → · This is the American opening of the Cold War; see the Cold War timeline for the full global rivalry, from Berlin and Korea to the missile crisis and beyond.
- 1954-1965Well documented
Primary source · 3 sourceswhy?
Best source: Brown v. Board of Education (1954)
Cited as a "primary" source (no stronger domain match).Brown v. Board and the Civil Rights Movement
On May 17, 1954, a unanimous Supreme Court ruled in Brown v. Board of Education that separate educational facilities are inherently unequal, overturning the separate-but-equal doctrine of Plessy v. Ferguson and declaring segregated public schools unconstitutional. The decision, bundling five cases begun by the NAACP, energized a mass movement against Jim Crow. Over the next decade, boycotts, sit-ins, freedom rides, and marches, met with violence and mass arrests, forced the issue onto the national agenda. The movement's pressure produced two great federal laws: the Civil Rights Act, signed by President Lyndon Johnson on July 2, 1964, which prohibited discrimination in public places and employment, and the Voting Rights Act of 1965, which outlawed the literacy tests and other devices used to keep Black Americans from voting.
Why it matters: The civil rights movement dismantled the legal structure of segregation and disenfranchisement that had stood since the end of Reconstruction, finally beginning to redeem the promises of the Fourteenth and Fifteenth Amendments nearly a century after they were written. Its laws and its tactics reshaped American democracy and became a model for later movements for equality.
How we know: The Brown decision and the 1964 and 1965 civil rights laws survive in the National Archives and the U.S. Reports, and the movement is documented in an enormous record of contemporary news coverage, government files, and participants' accounts.
Brown v. Board decided: May 17, 1954, unanimously · Overturned: Plessy v. Ferguson's separate but equal · Civil Rights Act: July 2, 1964 · Voting Rights Act: August 6, 1965
SourcesRelated timelines- The Civil Rights Movement → · This is the national-spine view; see the Civil Rights Movement timeline for Montgomery, Birmingham, the March on Washington, Selma, and the movement's leaders and turning points.
- 1964-1975Well documented
Primary source · 2 sourceswhy?
Best source: Tonkin Gulf Resolution (1964)
Cited as a "primary" source (no stronger domain match).The Vietnam War Divides the Country
Cold War containment drew the United States into a long war in Vietnam. After reported attacks on U.S. destroyers, Congress passed the Gulf of Tonkin Resolution on August 7, 1964, authorizing the president to take all necessary measures, and the Johnson administration escalated to hundreds of thousands of American troops. The war ground on for years without victory, and opposition grew at home. Protests spread across campuses and cities, and the shooting deaths of four students at Kent State University on May 4, 1970, became a symbol of the divide. A peace agreement was signed on January 27, 1973, and American forces withdrew, but the war ended only when North Vietnamese tanks rolled into Saigon on April 30, 1975. The National Archives records 58,220 U.S. military fatal casualties of the war.
Why it matters: Vietnam shattered public trust in the government and the military and left a lasting caution about foreign wars that shaped American politics for decades. The gap between official optimism and battlefield reality, the credibility gap, and the bitter divisions over the draft and the protests marked a generation and changed how Americans view their leaders and their wars.
How we know: The Gulf of Tonkin Resolution and the war's casualty statistics survive in the National Archives, and the escalation, protests, peace agreement, and fall of Saigon are documented in State Department histories and an extensive contemporary and archival record.
Gulf of Tonkin Resolution: August 7, 1964 · Kent State shootings: May 4, 1970 (four students killed) · Paris Peace Accords: January 27, 1973 · U.S. military dead: 58,220
- July 20, 1969Well documented
Primary source · 3 sourceswhy?
Best source: Apollo 11 Mission Overview
Cited as a "primary" source (no stronger domain match).Apollo 11 Lands on the Moon
The Cold War rivalry with the Soviet Union extended into space, and after the shock of Soviet firsts, President Kennedy set the goal in 1961 of landing an American on the Moon and returning him safely before the decade was out. On July 20, 1969, Apollo 11's lunar module Eagle touched down in the Sea of Tranquility. Neil Armstrong stepped onto the surface and spoke the words one small step for a man, one giant leap for mankind, becoming the first human to walk on the Moon, followed by Buzz Aldrin, while Michael Collins orbited above in the command module. An estimated hundreds of millions of people watched on television. The crew returned safely, splashing down on July 24, 1969.
Why it matters: The Moon landing was the crowning achievement of the space race and a demonstration of American technological and industrial power at the height of the Cold War. It fulfilled Kennedy's pledge, gave the United States a decisive symbolic victory over the Soviet Union, and remains one of the most watched and remembered events of the twentieth century.
How we know: Apollo 11 is documented in NASA's mission records, telemetry, film and television footage, and the lunar samples the crew returned, all preserved and studied by NASA.
Landing: July 20, 1969, Sea of Tranquility · First to walk on the Moon: Neil Armstrong, then Buzz Aldrin · In orbit above: Michael Collins · Goal set by: President Kennedy in 1961
Sources- NASA. Apollo 11 Mission Overview · primary
- NASA. Apollo 11 · primary
- HISTORY. Moon Landing 1969 · reference
Related timelines- Space Exploration → · See the Space Exploration timeline for the wider space race, the Apollo program, and what came before and after the Moon landing.
- 1981-1991Well documented
Primary source · 2 sourceswhy?
Best source: Remarks on East-West Relations at the Brandenburg Gate in West Berlin
Cited as a "primary" source (no stronger domain match).Reagan and the End of the Cold War
Ronald Reagan won the presidency in 1980 and served from 1981 to 1989, promising tax cuts, a military buildup, and a tougher line against the Soviet Union, which he called an evil empire. Standing at the Berlin Wall on June 12, 1987, he challenged the Soviet leader directly: Mr. Gorbachev, tear down this wall. As Mikhail Gorbachev loosened Soviet control, the communist governments of Eastern Europe fell in 1989, and the Berlin Wall was breached in November of that year. The Soviet Union itself dissolved at the end of 1991. On December 25, 1991, the Soviet hammer and sickle flag was lowered for the last time over the Kremlin and replaced by the Russian tricolor, ending both the Soviet state and the Cold War that had defined world politics for more than four decades.
Why it matters: The end of the Cold War left the United States as the world's sole superpower and closed the era of nuclear standoff between two blocs. It also opened debates that continue about how much credit belongs to American pressure, to Soviet reformers, and to the internal failures of the communist system, and about what role the United States should play in a world without a rival superpower.
How we know: Reagan's Brandenburg Gate speech survives in the Reagan Presidential Library archives, and the collapse of the Soviet Union is documented in the State Department's diplomatic history and the contemporaneous record of 1989 to 1991.
Reagan presidency: 1981-1989 · Berlin Wall speech: June 12, 1987 · Berlin Wall breached: November 1989 · Soviet Union dissolved: December 25, 1991
SourcesRelated timelines- The Cold War → · This is the American close of the Cold War; see the Cold War timeline for the full arc of the rivalry and the events across the world that brought it to an end.
- September 11, 2001Well documented
Primary source · 3 sourceswhy?
Best source: September 11, 2001 Timeline
Cited as a "primary" source (no stronger domain match).September 11 and the War on Terror
On the morning of September 11, 2001, four commercial airliners were hijacked. Two were flown into the twin towers of the World Trade Center in New York, which collapsed; a third struck the Pentagon outside Washington; and the fourth, United Flight 93, crashed in a field near Shanksville, Pennsylvania, after passengers fought back to stop it reaching Washington. Nearly 3,000 people were killed, the deadliest attack on American soil in the nation's history. The al-Qaeda network led by Osama bin Laden was responsible. In response the United States launched what it called the War on Terror, invading Afghanistan in October 2001 to remove the Taliban government that had sheltered al-Qaeda, and invading Iraq in 2003. The wars that followed lasted about two decades.
Why it matters: September 11 reshaped American life, foreign policy, and law: it led to two long wars, a vast expansion of surveillance and security powers, and a lasting sense of vulnerability. Debates over the wars, over torture and detention, over the balance between security and liberty, and over the costs and results of two decades of conflict have defined much of American politics in the twenty-first century.
How we know: The attacks are documented in an enormous record, including the official 9/11 Commission Report, and the timeline and casualties are preserved by the National Park Service at the Flight 93 National Memorial.
Date: September 11, 2001 · Deaths: Nearly 3,000 · Targets: World Trade Center, Pentagon, and Flight 93 · Response: Wars in Afghanistan (2001) and Iraq (2003)
Sources