(Redirected from 9 September
- 1776 - The Continental Congress officially names their new union of sovereign states the United States.
- 1791 - Washington, D.C., the capital of the United States, is named for President George Washington.
- 1839 - John Herschel takes the first glass plate photograph.
- 1850 - California is admitted as the thirty-first U.S. state.
- 1923 - Mustafa Kemal Atatürk, the founder of the Republic of Turkey, founds the Republican People's Party (CHP).
- 1943 - World War II: The Allies land at Salerno and Taranto, Italy.
- 1971 - The four-day Attica Prison riot begins, which eventually results in 39 dead, most killed by state troopers retaking the prison.
- 1991 - Tajikistan gains independence from the Soviet Union.
- 1993 - The Palestine Liberation Organization officially recognizes Israel.
- 2001 - Ahmed Shah Massoud, leader of the Afghan Northern Alliance, is assassinated in Afghanistan.