Events
- 1637 – Pequot War: Combined Puritan and Mohegan forces under English Captain John Mason attacked a Pequot fortified village in Mystic Connecticut, massacring approximately 500 Native Americans.
- 1647 – Alse Young becomes the first person executed as a witch in the American colonies, when she is hanged in Hartford, Connecticut.
- 1830 – The Indian Removal Act is passed by the U.S. Congress; it is signed into law by President Andrew Jackson two days later.
- 1864 – Montana is organized as a United States territory.
- 1865 – American Civil War: Confederate General Edmund Kirby Smith, commander of the Confederate Trans-Mississippi division, is the last general of the Confederate Army to surrender, at Galveston, Texas.
- 1868 – The impeachment trial of President Andrew Johnson ends, with Johnson being found not guilty by one vote.
- 1869 – Boston University is chartered by the Commonwealth of Massachusetts
- 1896 – Charles Dow publishes the first edition of the Dow Jones Industrial Average.
- 1896 – James Dunham murders six people in Campbell, California.
- 1917 – A powerful F4 tornado rips Mattoon, Illinois apart, killing 101 persons and injuring 689. It was the world's longest-lasting tornado, lasting for over 7 hours and traveling 293 miles, spreading death and destruction along its path.
- 1938 – The House Un-American Activities Committee begins its first session.
- 1948 – The U.S. Congress passes Public Law 557 which permanently establishes the Civil Air Patrol as an auxiliary of the United States Air Force.
- 1969 – Apollo program: Apollo 10 returns to earth after a successful eight-day test of all the components needed for the forthcoming first manned moon landing.
- 1972 – The United States and the Soviet Union sign the Anti-Ballistic Missile Treaty.
- 1977 – George Willig climbs the South Tower of New York City's World Trade Center.
- 1978 – In Atlantic City, New Jersey, Resorts International, the first legal casino in the eastern United States, opens.
- 1992 – Charles Geschke, co-founder of Adobe Systems, Inc. was kidnapped at gunpoint from the Adobe parking lot in Mountain View, California for $650,000 and is held hostage in a rented house in Hollister, California. The FBI rescues him four days later.
- 1998 – The U.S. Supreme Court rules that Ellis Island, the historic gateway for millions of immigrants, is mainly in the state of New Jersey, not New York.
- 2002 – The Mars Odyssey finds signs of huge water ice deposits on the planet Mars.
- 2004 – The New York Times publishes an admission of journalistic failings, claiming that its flawed reporting and lack of skeptism towards sources during the buildup to the 2003 war in Iraq helped promote the belief that Iraq possessed large stockpiles of weapons of mass destruction.
- 2004 – The U.S. Army veteran Terry Nichols is found guilty of 161 state murder charges for helping carry out the Oklahoma City bombing.
- 2006 – The 2006 Java earthquake kills over 5,700 people, leaves 200,000 homeless.