Wikipedia:Selected anniversaries/January 15
- 1759 - The British Museum opened.
- 1919 - Róża Luksemburg and Karl Liebknecht, two of the most prominent socialists in Germany, were tortured and murdered by the Freikorps.
- 1943 - Construction of the world's largest office building, The Pentagon, was completed.
- 1967 - The Green Bay Packers defeated the Kansas City Chiefs in the American football championship game now known as Super Bowl I.
- 2001 - The English Wikipedia, a Wiki free content encyclopedia, was officially launched.
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