On May 31

An extremely large, powerful, and erratic tornado struck Central Oklahoma, killing eight people and injuring more than 150 others.

American physician George Tiller, one of the few doctors in the country who performed late-term abortions, was shot and killed by Scott Roeder, an anti-abortion activist.

A Vanity Fair article revealed that the secret informant known as "Deep Throat", who had provided information about the Watergate scandal, was former FBI associate director Mark Felt (pictured).

An organized mob of police and government-sponsored Sinhalese paramilitary forces began three days of attacks that led to the burning of the Jaffna Library in Sri Lanka.

The United Kingdom completed its re-occupation of Iraq, returning Abd al-Ilah to power as regent for Faisal II.

German forces dropped four bombs on neutral Ireland, killing 28 people and damaging the residence of the President of Ireland.

A magnitude-7.7 earthquake struck Balochistan in British India, now part of Pakistan, killing between 30,000 and 60,000 people.

The Second Boer War came to an end with the signing of the Treaty of Vereeniging in Pretoria, South Africa.

The Ulm Minster, the world's tallest church building, is completed in Ulm, Germany.

American Civil War: Confederate troops under Joseph E. Johnston and G. W. Smith engaged Union forces under George B. McClellan at the Battle of Seven Pines outside Richmond, Virginia.

American Revolution: The Committee of Safety of Mecklenburg County, North Carolina, adopted the Mecklenburg Resolves, which annulled and vacated all laws originating from the authority of the King or Parliament.

Cardinal Bessarion (pictured) announced his donation of 746 Greek and Latin codices to the Republic of Venice, forming the Biblioteca Marciana.

Majapahit forces under Raden Wijaya won a major victory in the Mongol invasion of Java, now considered to be the founding date of the Indonesian city of Surabaya.

Mongol invasion of Kievan Rus': Mongol forces defeated a Kievan Rus' army at the Battle of the Kalka River in present-day Ukraine.

A Mongol army under Genghis Khan captures Zhongdu (modern Beijing), the capital of the Jin dynasty.

Petronius Maximus, the ruler of the Western Roman Empire, was stoned to death by a mob as he fled Rome ahead of the arrival of a Vandal force that sacked the city.