May 13th

Two suicide bombers attacked paramilitary police recruits heading home after months of training in northwest Pakistan, killing 87 people in what the Pakistan Taliban called revenge for the U.S. slaying of Osama bin Laden.
Terrorist incidents in Pakistan in 2011
The government unveiled a new version of the $20 bill - the first to be colorized in an effort to thwart counterfeiters.
The Falun Gong movement had its beginning as the sect's founder, Li Hongzhi, began publicly lecturing on his spiritual philosophy in the northeastern Chinese city of Changchun.
Falun Gong
Thousands of students begin a hunger strike on Tiananmen Square in Beijing. The non-violent occupation of the square was part of anti-corruption and pro-democracy demonstrations. Some 3000 unarmed civilians were killed when the army cracked down on the protesters on June 3-4, 1989.
Tiananmen Square protests of 1989
Philadelphia police dropped an explosive onto the headquarters of the radical group MOVE. 11 people died in the resulting fire.
Pope John Paul II survives an assassination attempt. Turkish right-wing extremist Mehmet Ali Ağca fired two shots at John Paul II on St. Peter's Square. The Pope was seriously wounded but survived thanks to a 5-hour operation and went on to visit his attacker in prison.
Pope John Paul II assassination attempt
Tennis male chauvinist Bobby Riggs defeated Margaret Smith Court, 6-2, 6-1 in front of a world-wide television audience. He would lose to Billie Jean King later that year.
Vice President Richard Nixon's limousine was battered by rocks thrown by anti-U.S. demonstrators in Caracas, Venezuela.
Phil Ochs
The first Formula One World Championship season kicks off. Giuseppe Farina won the first FIA World Championship of Drivers for the Alfa Romeo team.
1950 Formula One season
Igor Sikorsky pilots his VS-300 helicopter's maiden flight. The helicopter was the first successful model to use the single vertical tail rotor that most helicopters feature today.
Vought-Sikorsky VS-300
Louis Armstrong and his orchestra recorded the New Orleans's jazz classic, When the Saints Go Marching In, on Decca Records.
When the Saints Go Marching In
Great dustbowl storm sweeps across US prairies.
Dust Bowl
Three peasant children near Fatima, Portugal, reported seeing a vision of the Virgin Mary.
Our Lady of Fátima
Boxing champion Joe Louis was born in Lafayette, Ala.
Joe Louis
The Giro d'Italia cycle race is held for the first time. The Giro is considered one of the world's most important cycle races. Luigi Ganna won the first edition, which went from Milan to Naples and back.
Giro d'Italia
The United States formally declared war on Mexico after several days of fighting.
Mexican–American War
Composer Arthur Sullivan, who collaborated with William Gilbert in writing 14 comic operas, was born in London.
Gilbert and Sullivan
Republic of Ecuador is founded, with Juan Jose Flores as president.
Juan José Flores
Arthur Phillip sets sails with 11 ships of criminals to Botany Bay, Australia.
First Fleet
An English colony was settled at Jamestown in present-day Virginia.
Jamestown, Virginia
Mary Queen of Scots was defeated at the Battle of Langside and immediately fled to North England.
Battle of Langside