- Sep 10 Youssef Aftimus, Lebanese civil engineer and architect (b. 1866)
- Sep 14 Alexander Xaver Gwerder, Swiss writer, commits suicide at 29
- Sep 18 Hippoliet Daeye, Flemish painter (Dreamy), dies
- Sep 19 Giuseppe Zoppi, Swiss writer (Presento il mio Ticino), dies at 56
- Sep 22 Kaarlo Juho Ståhlberg, first President of Finland (b. 1865)
- Sep 22 Ian Hay [John Hay Beith], British novelist and playwright (Pip, Carrying On), dies at 76
- Sep 26 George Santayana, US philosopher/poet (Last Puritan), dies at 88
- Sep 30 Waldorf Astor, House of Lords & Commons/owner of Observer, dies