1. 1896: The first modern Olympic Games were inaugurated in Athens, Greece.

2. 1917: The United States formally declared war on Germany, entering World War I.

3. 1930: Mahatma Gandhi led the Salt March, a nonviolent protest against the British salt monopoly in colonial India.

4. 1968: American civil rights leader Martin Luther King Jr. was assassinated in Memphis, Tennessee.

5. 1971: Soviet cosmonauts launched Soyuz 10 on the first mission to board the world’s first space station, Salyut 1.

6. 1994: The Rwandan Genocide began, resulting in the massacre of hundreds of thousands of Tutsis and moderate Hutus by extremist Hutu militias.

7. 2009: A magnitude 6.3 earthquake struck L’Aquila, Italy, killing over 300 people and causing widespread damage.

8. 2014: A gunman opened fire at the Fort Hood military base in Texas, killing three people and injuring 16 others before committing suicide.

9. 2017: The United States launched a missile strike on a Syrian airbase in response to a chemical weapons attack on civilians in Khan Shaykhun, Syria.

10. 2020: The International Olympic Committee announced the postponement of the 2020 Summer Olympics in Tokyo, Japan, due to the COVID-19 pandemic.