Wikipedia launches as an open, editable encyclopedia
A failed expert-reviewed project pivots to letting anyone write an article, with no review at all
Quick facts
- Founders
- Jimmy Wales and Larry Sanger
- Launched
- 15 January 2001
- Predecessor project
- Nupedia (expert peer review, launched 2000)
- Growth
- More than 20,000 articles in 18 languages within a year
What happened
Jimmy Wales and Larry Sanger had been running Nupedia, a free online encyclopedia whose articles were written by credentialed experts and passed through a slow, formal peer-review process. In its first six months, Nupedia had published only two articles. Sanger proposed adding a wiki, software that lets any visitor edit a page directly in a web browser, as a faster way to draft material for Nupedia's review queue. That side project, launched 15 January 2001 and named Wikipedia, a blend of 'wiki' and 'encyclopedia,' let anyone write or edit an article with no review at all. It had more than 20,000 articles across 18 languages by the end of its first year.
Why it matters
Open, unreviewed editing, the opposite of Nupedia's slow expert gatekeeping, is precisely what let Wikipedia grow so fast, and it remains the reason the site struggles with vandalism and accuracy even as it became the internet's most consulted general reference. Its scale forced SourcedStory and every serious reference project since to reckon with a tertiary source that is enormously useful as a map to citations and unusable as a citation itself.
How we know
HISTORY's own account of the January 2001 launch describes Nupedia's failure, the two-article count in its first six months, and Wikipedia's growth to 20,000 articles by its first anniversary.
Sources
- HISTORY (A&E Networks). Wikipedia launches · Reputable sourcehistory.com · The domain "history.com" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- Internet Hall of Fame. Jimmy Wales · General sourceinternethalloffame.org · Cited as a "reference" source (no stronger domain match).
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