On this day in history

1804: The Lewis and Clark Expedition officially departs from St. Charles, Missouri.
1863: Union General Ulysses S. Grant's second attack on Vicksburg fails and a siege begins.
1868: The "Great Train Robbery" takes place as seven members of the Reno Gang make off with $98,000 in cash from a train's safe in Indiana.
1908: The Wright brothers register their flying machine for a U.S. patent.
1939: Adolf Hitler and Benito Mussolini sign a "Pact of Steel" forming the Axis powers.
1947: The Truman Doctrine brings aid to Turkey and Greece.
1967: The children's program Mister Rogers' Neighborhood premiers.
1972: Ceylon becomes the Republic of Sri Lanka as its constitution is ratified.
1985: Baseball player Pete Rose passes Hank Aaron as National League run scoring leader with 2,108.
1992: Johnny Carson's final appearance on The Tonight Show on NBC, after 30 years as the program's host.
2004: Fahrenheit 9-11, directed by Michael Moore, becomes the first documentary ever to win the Palme d'Or at the Cannes Film Festival.
2011: An EF5 tornado kills at least 158 people in Joplin, Missouri, the largest death toll from a tornado since record-keeping began in 1950.
2015: The Republic of Ireland, long known as a conservative, predominantly Catholic country, becomes the first nation in the world to legalize gay marriage in a public referendum.

Source: HistoryNet.com