1812: The United States declares war on Great Britain, beginning the War of 1812.
1846: The United States declares war on Mexico, beginning the Mexican-American War.
1863: The Battle of Gettysburg begins, marking the turning point in the Civil War.
1940: Paris falls to the German army during World War II.
1955: Emmett Till, a 14-year-old African-American boy, is brutally murdered in Mississippi, sparking the Civil Rights Movement.
1963: The Civil Rights Act of 1963 is signed into law, prohibiting discrimination on the basis of race, color, religion, sex, or national origin.
1972: The United States Supreme Court rules in Roe v. Wade that the Constitution protects a woman's right to have an abortion.
1981: The AIDS epidemic is first recognized when five cases of a rare type of pneumonia are reported in Los Angeles.
1991: Mount Pinatubo in the Philippines erupts, causing significant climate change and displacement of millions of people.
2016: The United Kingdom votes to leave the European Union, commonly referred to as Brexit.
2021: After over two decades, the United States fully withdraws its troops from Afghanistan.