- Oct 2 NY Hayden Planetarium, 4th in US, opens
- Oct 3 Italy invades Ethiopia, starting the Second Italo-Ethiopian War
- Oct 6 Italian army occupies Adua Abyssinia
- Oct 6 Market Street Railway, San Francisco, starts using trackless trolley coaches
- Oct 7 Baseball World Series: Detroit Tigers beat Chicago Cubs, 4-3 at Navin Field for 4 games to 2 series win; Tigers win first championship in 5 WS appearances
- Oct 10 Coup under Gen Giorgios Kondylis in favor of Greek monarchy
Music History
Oct 10 George Gershwin's "Porgy & Bess" opens on Broadway NY
- Oct 10 League of Nations denounces Italian invasion of Abyssinia
Music Premiere
Oct 12 Cole Porter's musical "Jubilee" opens at the Imperial Theatre, NYC; runs for 167 performances
Historic Event
Oct 19 Mao Zedong's army reaches Shanxi
Sports History
Oct 20 Detroit Tigers future Baseball Hall of Fame first baseman Hank Greenberg is named AL MVP by the BWAA; Boston Red Sox pitcher Wes Ferrell is runner-up
- Oct 20 Communist forces end their Long March at Yan'an, in Shaanxi, China, bringing Mao Zedong to prominence
- Oct 22 PGA Championship Men's Golf, Twin Hills CC: Johnny Revolta wins his only major title, defeating Tommy Armour, 5 & 4
- Oct 22 Establishment of the rank of Marshal of the Soviet Union
- Oct 23 Gabby Hartnett selected NL MVP
- Oct 23 Dutch Schultz, Abe Landau, Otto Berman, and Bernard "Lulu" Rosencrantz are fatally shot at a saloon in Newark, New Jersey in what becomes known as The Chophouse Massacre.
Election of Interest
Oct 23 Mackenzie King is elected as Prime Minister of Canada for the third time