1513: Spanish explorer Juan Ponce de Leon landed in Florida. He had sighted the land the day before.
1776: George Washington received an honorary Doctor of Laws degree from Harvard College.
1829: James Carrington patented the coffee mill.
1882: The American outlaw Jesse James was shot in the back and killed by Robert Ford for a $5,000 reward. There was later controversy over whether it was actually Jesse James that had been killed.
1910: Alaska's Mt. McKinley, the highest mountain in North America, was climbed.
1948: U.S. President Harry Truman signed the Marshall Plan to revive war-torn Europe. It was $5 billion in aid for 16 countries.
1953: TV Guide was published for the first time.
1968: Martin Luther King Jr. delivered his "mountaintop" speech just 24 hours before he was assassinated.
1986: The U.S. national debt hit $2 trillion.
1996: Unabomber suspect Theodore Kaczynski was arrested. He pled guilty in January 1998 to five unabomber attacks in exchange for a life sentence without chance for parole.
1998: The Dow Jones industrial average climbed above 9,000 for the first time.
2000: A U.S. federal judge ruled that Microsoft had violated U.S. antitrust laws by keeping "an oppressive thumb" on its competitors. Microsoft said it would appeal the ruling.
2000: The Nasdaq set a one-day record when it lost 349.15 points to close at 4,233.68.
2010: The first iPad was released.