On this day in 1965, Edward H. White II emerged from the orbital spacecraft Gemini 4 during its third orbit and floated in space for about 20 minutes, thus becoming the first American astronaut to walk in space.
| 1967: | | The Six-Day War, the third of the Arab-Israeli wars, began. |
|
| 1947: | | | In an address at Harvard University, U.S. Secretary of State George C. Marshall advanced the idea of the Marshall Plan, a European self-help program to be financed by the United States. |
|
| 1944: | | In World War II, Allied forces entered Rome. |
|
| 1939: | | | Canadian politician Joe Clark, who in 1979 became the country's youngest prime minister, was born. |
|
| 1883: | | | English economist, journalist, and financier John Maynard Keynes, best known for his revolutionary economic theories (Keynesian economics) on the causes of prolonged unemployment, was born. |
|
| 1849: | | The absolute monarchy in Denmark was abolished and replaced by a new constitution that established a constitutional monarchy with a parliament, as well as freedom of the press, religious freedom, and the right to hold meetings and form associations. |
|
| 1723: | | Social philosopher and political economist Adam Smith was baptized in Kirkcaldy, Fife, Scotland. |
|