Wikipedia:Selected anniversaries/September 15
September 15: Independence Day for Costa Rica, Guatemala, Honduras, Nicaragua and El Salvador (1821)
- 1831 - The John Bull (pictured), currently the oldest operable steam locomotive in the world, ran for the first time.
- 1835 - Aboard HMS Beagle, Charles Darwin reached the Galápagos Islands, where he began to develop his theories of evolution.
- 1916 - Tanks, the "secret weapons" of the British Army during World War I, were first used in combat at the Battle of the Somme.
- 1935 - Nazi Germany enacted the Nuremberg Laws, which deprived German Jews of citizenship, and adopted a new national flag emblazoned with a swastika.
- 1950 - Korean war: U.S. armed forces landed at Incheon, Korea.
Recent days: September 14 – September 13 – September 12