May 31st

The widest tornado ever recorded hits El Reno, Oklahoma. The storm had a width of 4.2 km (2.6 mi). Nine people were killed as it swept over rural areas of Central Oklahoma.
2013 El Reno tornado
Nine people are dead after an Israeli navy commando attacks a flotilla of cargo ships and passenger boats on their way to Gaza to provide aid and supplies for the area.
Gaza flotilla raid
Dr. George Tiller, a provider of late-term abortions, was shot and killed in a Wichita, Kan., church. (Gunman Scott Roeder was later convicted and sentenced to life in prison.).
Assassination of George Tiller
Usain Bolt breaks the world record in the 100m sprint, with a wind-legal (+1.7m/s) 9.72 seconds.
Deep Throat reveals himself. Former FBI agent Mark Felt admitted that he was the most important informant in the 1970's Watergate scandal which uncovered the dirty tricks of the Nixon administration, ultimately leading to Nixon's resignation.
Deep Throat (Watergate)
Alberta Martin, 97, one of the last widows of a U.S. Civil War veteran, died. She had married Confederate veteran William Martin in 1927 when she was 21 and he was 81.
Alberta Martin
Eric Rudolph, suspected in bombings at a Birmingham. Ala., abortion clinic and at the Atlanta Olympics, was arrested outside a grocery store in Murphy, N.C. (He later pleaded guilty and was sentenced to four life terms.).
Eric Rudolph
The United States announced it was no longer aiming long-range nuclear missiles at targets in the former Soviet Union.
North Korea and weapons of mass destruction
Leaders of Angola's two warring factions signed a peace treaty, ending a 16-year civil war.
Mozambican Civil War
The sitcom "Seinfeld" premiered on NBC.
The trans-Alaska oil pipeline was completed after three years of work.
Trans-Alaska Pipeline System
An earthquake in Peru left more than 50,000 dead.
1970 Ancash earthquake
Gestapo official Adolf Eichmann was hanged in Israel for his role in the Holocaust.
Adolf Eichmann
South Africa becomes an independent republic. Following international criticism of the country's Apartheid regime, it had to leave the Commonwealth of Nations. The system of racial segregation was gradually abolished in the early 1990s.
South African republic referendum, 1960
Communists seize power in Hungary.
Hungarian parliamentary election, 1947
7.7 magnitude earthquake hits Quetta in Balochistan, British Raj (Pakistan) killing approx 50,000.
Battle of Jutland (Skagerrak): naval battle between British Grand Fleet and German High Seas Fleet: over 8,500 die in this inconclusive slaughter - although the German fleet never put to sea again.
Battle of Jutland
The 17th Amendment to the Constitution, providing for the popular election of U.S. senators, was declared in effect.
Seventeenth Amendment to the United States Constitution
The hull of the Titanic was launched in Belfast. At the ceremony, a White Star Line employee claimed, “Not even God himself could sink this ship.”.
History of the Port of Southampton
Union of South Africa declares its independence from the United Kingdom.
Union of South Africa
Heavy rains caused the South Fork Dam to collapse, sending 20 million tons of water into Johnstown, Pa. Over 2,200 people were killed and the town was nearly destroyed.
Johnstown Flood
Werner von Siemens presents the world's first electric locomotive. Von Siemens' landmark invention was soon used in trams. 1881 saw the introduction of the world's first electric tram in Berlin, Germany.
Electric locomotive
The Great Clock housing Big Ben starts keeping time. The clock at the top of Elizabeth Tower at the north end of the British Houses of Parliament is one of the world's best-known timekeepers.
Big Ben
Poet Walt Whitman was born in West Hill, N.Y.
Walt Whitman
The first U.S. Copyright Law was enacted, protecting books, maps, and other original materials.
Copyright Act of 1790
Martin Frobisher sails from Harwich, England, to Frobisher Bay, Canada, eventually to mine fools gold, used to pave streets in London.