The Russo-Japanese War exposes the Tsar's army
Japan attacks before Russia even hears war has been declared, and the humiliation that follows helps trigger revolution at home.
Quick facts
- War dates
- 1904-1905
- Peace treaty
- Portsmouth, New Hampshire, September 1905
- Mediator
- US President Theodore Roosevelt
What happened
Russia and Japan went to war in 1904 over competing claims to Manchuria and Korea. Japan struck first, attacking the Russian fleet at Port Arthur before Russia had received formal notice that war had been declared, and won an early advantage. Russia sent its Baltic Fleet on a months-long voyage around Africa and Asia to reinforce the Pacific, only for the Japanese navy to destroy half of it on arrival. The war ended with the Treaty of Portsmouth, brokered by US President Theodore Roosevelt in New Hampshire in September 1905, which gave Japan control of Korea, southern Manchuria including Port Arthur, and the southern half of Sakhalin Island.
Why it matters
Losing to an Asian power that Russian officials had dismissed as inferior humiliated the imperial government and destroyed public confidence in the Tsar's competence just as economic strain and worker unrest were building at home. The defeat directly fed the uprising that broke out across Russia within months of the peace treaty.
How we know
The Office of the Historian at the US Department of State documents the war's course and the Portsmouth negotiations, since the United States brokered the peace; Roosevelt received the Nobel Peace Prize for his role.
Sources
- Office of the Historian, US Department of State. Treaty of Portsmouth and the Russo-Japanese War, 1904-1905 · Reputable sourcehistory.state.gov · The domain "history.state.gov" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- Office of the Historian, US Department of State. Treaty of Portsmouth and the Russo-Japanese War, 1904-1905 · Reputable sourcehistory.state.gov · The domain "history.state.gov" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
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