2013: An upsurge in violence in Iraq leaves more than 389 people dead over three days.
2010: Jessica Watson becomes the youngest person to sail, non-stop and unassisted around the world solo.
2008: California becomes the second U.S. state after Massachusetts in 2004 to legalize same-sex marriage after the state's own Supreme Court rules a previous ban unconstitutional.
2004: Arsenal F.C. go an entire league campaign unbeaten in the English Premier League, joining Preston North End F.C with the right to claim the title The Invincibles
1997: The United States government acknowledges the existence of the "Secret War" in Laos and dedicates the Laos Memorial in honor of Hmong and other "Secret War" veterans.
1991: Édith Cresson becomes France's first female premier.
1969: People's Park: California Governor Ronald Reagan has an impromptu student park owned by the University of California at Berkeley fenced off from student anti-war protestors, sparking a riot.
1966: After a policy dispute, Prime Minister Nguyễn Cao Kỳ of South Vietnam's ruling junta launches a military attack on the forces of General Tôn Thất Đính, forcing him to abandon his command.
1963: Project Mercury: The launch of the final Mercury mission, Mercury-Atlas 9 with astronaut Gordon Cooper on board. He becomes the first American to spend more than a day in space, and the last American to go into space alone.
1940: World War II: After fierce fighting, the poorly trained and equipped Dutch troops surrender to Germany, marking the beginning of five years of occupation.
1940: USS Sailfish is recommissioned. It was originally the USS Squalus.
1933: All military aviation organizations within, or under the control of, the RLM of Germany were officially merged in a covert manner, to form its Wehrmacht military's air arm, the Luftwaffe.
1925: Al-Insaniyyah, the first Arabic communist newspaper, is founded.
1919: Greek occupation of Smyrna. During the occupation, the Greek army kills or wounds 350 Turks; those responsible are punished by Greek commander Aristides Stergiades.
1905: Las Vegas is founded when 110 acres (0.45 km2), in what later would become downtown, are auctioned off.
1904: Russo-Japanese War: The Russian minelayer Amur lays a minefield about 15 miles off Port Arthur and sinks Japan's battleships Hatsuse, 15,000 tons, with 496 crew and Yashima.
1817: Opening of the first private mental health hospital in the United States, the Asylum for the Relief of Persons Deprived of the Use of Their Reason (now Friends Hospital, Philadelphia, Pennsylvania).
1718: James Puckle, a London lawyer, patents the world's first machine gun.
1648: The Treaty of Westphalia is signed.
1618: Johannes Kepler confirms his previously rejected discovery of the third law of planetary motion (he first discovered it on March 8 but soon rejected the idea after some initial calculations were made).
1536: Anne Boleyn, Queen of England, stands trial in London on charges of treason, adultery and incest; she is condemned to death by a specially-selected jury.
589: King Authari marries Theodelinda, daughter of the Bavarian duke Garibald I. A Catholic, she has great influence among the Lombard nobility.
392: Emperor Valentinian II is assassinated while advancing into Gaul against the Frankish usurper Arbogast. He is found hanging in his residence at Vienne.
221: Liu Bei, Chinese warlord, proclaims himself emperor of Shu Han, the successor of the Han dynasty.
495 BC: A newly constructed temple in honour of the god Mercury was dedicated in ancient Rome on the Circus Maximus, between the Aventine and Palatine hills. To spite the senate and the consuls, the people awarded the dedication to a senior military officer, Marcus Laetorius.