Soviet cosmonaut Yuri Gagarin orbits the Earth aboard Vostok 1, becoming the first human in space.
East German authorities begin erecting barriers, later a wall, sealing off West Berlin from East Berlin, a defining symbol of the Cold War.
Iran, Iraq, Kuwait, Saudi Arabia and Venezuela found the Organization of the Petroleum Exporting Countries at the Baghdad Conference.
Pope John XXIII opens the Second Vatican Council, which brings sweeping reforms to the Catholic Church.
A 13-day standoff between the United States and the Soviet Union over nuclear missiles in Cuba brings the world closest to nuclear war.
Valentina Tereshkova flies into orbit aboard Vostok 6, becoming the first woman in space.
Belgium, France, West Germany, Italy, Luxembourg and the Netherlands sign the treaty creating the European Economic Community, forerunner of the European Union.