- 1517 – Martin Luther posts his 95 Theses on the door of the Castle Church in Wittenberg.
- 1864 – Nevada is admitted as the 36th state.
- 1922 – Benito Mussolini is made Prime Minister of Italy.
- 1941 – The Mount Rushmore National Memorial in South Dakota was completed.
- 1968 – Vietnam War October Surprise: Citing progress with the Paris peace talks, President Lyndon B. Johnson announces to the nation he has ordered a complete cessation of “all air, naval, and artillery bombardment of North Vietnam” effective November 1.
- 1984 – Indian Prime Minister Indira Gandhi was assassinated outside her home by members of her own security force.
- 2002 – A federal grand jury indicts former Enron chief financial officer Andrew Fastow on 78 counts related to the collapse of the company.
- 2011 – The global population of humans reaches seven billion.