- Sep 2 Constantine Kanaris, Greek admiral, freedom fighter and politician (b. 1793)
- Sep 3 Adolphe Thiers, French statesman, 1st president of 3rd French Republic (1871-77), dies at 80
Crazy Horse
Sep 5 Crazy Horse [Tashunka Witko], last great Sioux war chief, dies at 37
- Sep 12 Julius Reitz, German cellist, composer, teacher, and music editor, dies at 64
William Henry Fox Talbot
Sep 17 William Henry Fox Talbot, English photographic pioneer, dies at 77
- Sep 23 Urbain JJ Leverrier, codiscoverer of Neptune, dies
- Sep 25 Carl Reinhold August Wunderlich, German Physician and advocate of scientific medicine, dies at 62
- Sep 26 Hermann Grassmann, German linguist and mathematician, dies at 68
- Sep 30 Toohoolhoolzote, prophet of Nez Perce indians, dies in battle