0030 - Jesus of Nazareth was crucified.
0313 - Licinius unified the whole of the eastern empire under his own rule.
1250 - King Louis IX of France was ransomed for one million dollars.
1527 - Henry VIII and King Francis of France signed the treaty of Westminster.
1725 - Spain withdrew from Quadruple Alliance.
1789 - George Washington took office as first elected U.S. president.
1803 - The U.S. purchased the Louisiana Territory from France for $15 million.
1812 - Louisiana admitted as the 18th U.S. state.
1849 - The republican patriot and guerrilla leader Giuseppe Garabaldi repulsed a French attack on Rome.
1864 - Work began on the Dams along the Red River. The work would allow Union General Nathaniel Banks' troops to sail over the rapids above Alexandria, Louisiana.
1889 - George Washington's inauguration became the first U.S. national holiday.
1900 - Hawaii was organized as an official U.S. territory.
1900 - Casey Jones was killed while trying to save the runaway train "Cannonball Express."
1930 - The Soviet Union proposed a military alliance with France and Great Britain.
1938 - Happy Rabbit appeared in the cartoon "Porky's Hare Hunt." This rabbit would later evolve into Bugs Bunny.
1939 - The first railroad car equipped with fluorescent lights was put into service. The train car was known as the "General Pershing Zephyr."
1939 - Lou Gehrig played his last game with the New York Yankees.
1940 - Belle Martell was licensed in California by state boxing officials. She was the first American woman, prizefight referee.
1943 - The British submarine HMS Seraph dropped 'the man who never was,' a dead man the British planted with false invasion plans, into the Mediterranean off the coast of Spain.
1945 - Adolf Hitler and Eva Braun committed suicide. They had been married for one day. One week later Germany surrendered unconditionally.
1945 - Arthur Godfrey began his CBS radio morning show "Arthur Godfrey Time." It ran until this day in 1972.
1947 - The name of Boulder Dam, in Nevada, was changed back to Hoover Dam.
1948 - The Organization of American States (OAS) held its first meeting in Bogota, Colombia. The institution's goal was to facilitate better relations between the member nations and to help prevent the spread of communism in the Western Hemisphere.
1952 - Mr. Potato Head became the first toy to be advertised on network television.
1953 - The British West Indian colonies agreed on the formation of the British Caribbean Federation that would eventually become a self-governing unit in the British Commonwealth.
1964 - The FCC ruled that all TV receivers should be equipped to receive both VHF and UHF channels.
1968 - U.S. Marines attacked a division of North Vietnamese in the village of Dai Do.
1970 - U.S. troops invaded Cambodia to disrupt North Vietnamese Army base areas. The announcement by U.S. President Nixon led to widespread protests.
1972 - The North Vietnamese launched an invasion of the South.
1973 - U.S. President Nixon announced resignation of Haldeman, Ehrlichman, and other top aides.
1975 - Communists North Vietnamese troops entered the Independence Palace of South Vietnam in Saigon. 11 Marines lifted off of the U.S. Embassy were the last soldiers to evacuate.
1980 - Terrorists seized the Iranian Embassy in London.
1984 - U.S. President Reagan signed cultural and scientific agreements with China. He also signed a tax accord that would make it easier for American companies to operate in China.
1991 - An estimated 125,000 people were killed in a cyclone that hit Bangladesh.
1993 - CERN put the World Wide Web software in the public domain.
1993 - Monica Seles was stabbed in the back during a tennis match in Hamburg, Germany. The man called himself a fan of second- ranked Steffi Graf. He was convicted of causing grievous bodily harm and received a suspended sentence.
1998 - NATO was expanded to include Poland, Hungary and the Czech Republic. The three nations were formally admitted the following April at NATO's 50th anniversary summit.
1998 - United and Delta airlines announced their alliance that would give them control of 1/3 of all U.S. passenger seats.
1998 - In the U.S., Federal regulators fined a contractor $2.25 million for improper handling of oxygen canisters on ValuJet that crashed in the Florida Everglades in 1996.
2002 - Pakistani President Pervez Musharraf was overwhelmingly approved for another five years as president.
2012 - One World Trade Center became the tallest structure in New York when it surpassed the height of the Empire State Building.
2015 - NASA's Messenger spacecraft crashed into the surface of Mercury. The space probe sent back more than 270,000 pictures to earth.