- The US Constitution went into effect. (1789) The US Constitution went into effect on this day as Congress had its first meeting in New York City. Though the US government had been operating under the Articles of Confederation for some years, the modern form of government in the US began on this day.
- The first case of Spanish flu was diagnosed (1918) This was the start of a massive pandemic that lasted for over three years and hit every continent. About a third of the world's population was infected with the disease, and about 100 million people died of it.
- Andrew Jackson held an open house. (1829) More than 20,000 people mobbed the White House, climbing on furniture and grinding mud and food into the carpets. The only way that the staff could draw them out was by placing large washtubs full of whiskey on the front lawn. The tradition of the presidential open house continued until Grover Cleveland's term in 1885, when he decided to opt for a parade instead.
- John Lennon claimed that the Beatles were "bigger than Jesus." (1966) The off-the-cuff remark sparked massive outrage in America, and was the first big blow to Beatlemania. Many DJs in the Bible belt stopped playing their records, and people held burning parties to burn their records and Beatles paraphernalia. Lennon later apologized for the remarks, saying he had been misunderstood.
- The FDA approved a blood test for AIDS. (1985) The test went on to be used to test all blood donations in the US, saving countless lives.
- The first socialist congressman in the US was elected. (1911) Victor Berger was a founding member of the Socialist Party of America, and was extremely controversial for introducing a pension scheme for the elderly, unemployment insurance, and public housing. He was later arrested for his anti-militarist views and sentenced to 20 years in prison, though the Supreme Court overturned the decision.
- The American Automobile Association (AAA) was founded. (1902) Now known for its road maps and discount books, the club was originally founded to help motorists find roads that were actually suitable for cars, which were few and far between at the time. The club also formed the backbone of driver's education with the first widely used driving manual Sportsmanlike Driving.
- Charlie Chaplin was knighted. (1975) Though many know Chaplin as the star of American silent films, he was actually born in Britain. He was said to be "dumbfounded" by the knighting ceremony, which was reportedly delayed until so late in his life because of his supposed Communist sympathies.
- Princess Elizabeth joined the Auxiliary Territorial Service (ATS). (1945) The ATS was much like the Women's Army Corps (WAC) in the US. Elizabeth, who would later become the queen, served in the ATS as a truck driver.
- Antonio Vivaldi was born. (1678) Though best known for his Four Seasons, Vivaldi was a prolific composer, and greatly influenced his fellow Baroque musicians. Though his work was popular during his lifetime, he died a pauper after a patron died on him.