- 1565 – Rio de Janeiro is founded.
- 1642 – Georgeana (York) in Maine becomes the first incorporated American city.
- 1692 – Salem Witch Hunt begins
- 1780 – Pennsylvania becomes the first US state to abolish slavery (for newborns only).
- 1781 – Articles of Confederation are (finally!) ratified after nearly four years of wrangling.
- 1790 – First US census authorized.
- 1803 – Ohio becomes the 17th state in the Union
- 1845 – President John Tyler signs a resolution annexing the Republic of Texas.
- 1864 – Rebecca Lee becomes the first Black woman in the US to receive a medical degree.
- 1872 – Yellowstone Park established
- 1875 – A Civil Rights bill is enacted by Congress, giving Blacks the right to equal treatment in “inns, public conveyances, theaters and other places of public amusement.” It is overturned by the US Supreme Court in 1883.
- 1879 – The telephone makes it to Utah.
- 1880 – Gillette Hayden, a pioneering dentist and periodontist, is born. She founded the American Academy of Periodontology and served as its president.
- 1896 – 80,000 Ethiopians destroy 20,000 Italians in Ethiopia, killing two generals and capturing General Matteo Albertone in the Battle of Adowa.
- 1910 – Two trains are swept into a canyon by an avalanche in Wellington, Washington, killing 96 people.
- 1924 – Harry Belafonte is born.
- 1932 – Lindbergh baby kidnapped.
- 1941 – Captain America created by cartoonists Joe Simon and Jack Kirby is first published by Timely Comics.
- 1954 – US explodes Castle Bravo, a 15 megaton hydrogen bomb at Bikini Atoll, which accidentally became the most powerful nuclear device ever detonated by the US.
- 1960 – San Antonio, Texas, becomes the first major Southern city to integrate lunch counters.
- 1961 – President Kennedy establishes the Peace Corps with Executive Order #10924
- 1966 – Soviet probe crashes into Venus
- 1967 – U.S. House expels Rep. Adam Clayton Powell Jr. Civil rights leaders say Powell was ousted because of his race.
- 1971 – Bomb explodes in US Capitol building.
- 1973 – Pink Floyd release their album “Dark Side of the Moon”, since sold over 45 million copies.
- 1987 – Congress passes a resolution designating March as Women’s History Month.
- 2020 – Turkey launches major offensive against Syrian government in northern Syria after 36 Turkish soldiers killed in air and artillery strikes 3 days earlier
