Soviet Air Force officer Stanislav Petrov identifies a report of an incoming nuclear missile as a computer error and not an American first strike, thus preventing nuclear war.
In Chicago, the first televised debate takes place between presidential candidates Richard M. Nixon and John F. Kennedy.
Korean War: United Nations troops recapture Seoul from North Korean forces.
Ukrainian War of Independence: The Revolutionary Insurgent Army of Ukraine defeats the White Russian Volunteer Army at the Battle of Peregonovka.
World War I: The Meuse-Argonne Offensive began which would last until the total surrender of German forces.
World War I: The Battle of Polygon Wood begins.
Four months after the 1907 Imperial Conference, New Zealand and Newfoundland are promoted from colonies to dominions within the British Empire.
Albert Einstein publishes the third of his Annus Mirabilis papers, introducing the special theory of relativity.
George Washington appoints Thomas Jefferson the first United States Secretary of State.
American Revolutionary War: British troops capture and begin the occupation of Philadelphia, which had been serving as the American capital city, during the Philadelphia campaign.
The city council of Amsterdam votes to support William of Orange's invasion of England, which became the Glorious Revolution.