1. 1865: General Robert E. Lee surrenders to General Ulysses S. Grant, effectively ending the American Civil War, at the Appomattox Court House in Virginia.

2. 1939: Singer Marian Anderson performs a historic concert on the steps of the Lincoln Memorial in Washington, D.C., after being denied permission to sing at Constitution Hall due to her race.

3. 1940: Germany invades Denmark and Norway during World War II, marking the beginning of the Norwegian Campaign.

4. 1959: NASA introduces the first seven astronauts selected for the American space program, known as the “Mercury Seven”.

5. 1965: The Astrodome, the world’s first multi-purpose domed sports stadium, opens in Houston, Texas.

6. 1983: The space shuttle Challenger makes its maiden voyage into space, marking the beginning of its operational career.

7. 1991: Georgia declares independence from the Soviet Union, leading to the eventual dissolution of the USSR.

8. 2003: Iraqis seize control of a Saddam Hussein statue in Baghdad’s Firdos Square, symbolizing the fall of the regime during the Iraq War.

9. 2019: Scientists release the first-ever image of a black hole, captured by the Event Horizon Telescope.

10. 2020: British Prime Minister Boris Johnson is hospitalized due to COVID-19 complications, highlighting the severity of the global pandemic.