September 11 is the 254th day of the year (255th in leap years). There are 111 days remaining.
- 1711: William Boyce (composer)
- 1885: D.H. Lawrence (novelist)
- 1948: John Martyn (musician)
- 1967: Harry Connick, Jr. (singer)
- 1971: Former Soviet Premier Nikita Krushchev dies of a heart attack.
- 1973: Chilean President Salvador Allende dies in a violent coup.
- 1978: Janet Parker, a medical photographer, is the final victim of smallpox (contracted in a lab accident).
- 1987: Lorne Greene, actor, of pneumonia.
- 1994: Actress Jessica Tandy
- 2001: September 11 Terrorist Attack/Casualties
- 1609: First European (Henry Hudson) sets foot on Manhattan island.
- 1973: Chilean armed forces headed by General Augusto Pinochet take control of the country in a coup d'etat against President Salvador Allende. Allende dies in the Palace of Goverment.
- 1978: The Television series "Mork and Mindy" premieres.
- 1997: Scotland voted to create its own Parliament after 290 years of union with England.
- 1998: Independent counsel Kenneth Starr sent a report to the US Congress accusing President Bill Clinton of 11 possible impeachable offenses.
- 2001: Two aircraft crash into the World Trade Center in New York City within minutes of each other; the World Trade Center towers collapse. Another plane crashes into the Pentagon, destroying a section. A fourth plane crashes outside of Pittsburgh. See September 11, 2001 Terrorist Attack for more information.