- February 14 - Oregon becomes the 33th state of the United States
- June 24 - Battle of Solferino (Battle of the Three Sovereigns) Sardinia and Napoleon III of France defeat Franz Joseph I of Austria in northern Italy
- July 11 - A Tale Of Two Cities by Charles Dickens is published
- September 17 - Joshua A. Norton proclaimes himself "Emperor of These United States"
- Charles Darwin publishes The Origin of Species
- Karl_XV succeeds Oskar I as Swedish King
- The Sinaiticus codex was found by Dr. Tischendorf on his third visit to the convent of St. Catherine, on Mount Sinai
- Bernhard Riemann formulates the Riemann hypothesis, one of most important open problems of contemporary mathematics
- May 22 - Sir Arthur Conan Doyle, British writer of the Sherlock Holmes novels
- October 18 - Henri Bergson, French philosopher and winner of the 1927 Nobel Prize in literature
- September 15 - Isambard Kingdom Brunel, British engineer.
- November 28 - Washington Irving, American author.
- December 2 - John Brown, American abolitionist