On May 4

The Parliament of Malta moved from the Grandmaster's Palace to the purpose-built Parliament House (pictured).

Ken Livingstone took office as the first mayor of London.

Falklands War: HMS Sheffield was struck by an Exocet missile, killing 20 sailors and leading to its sinking six days later—the first Royal Navy ship sunk in action since World War II.

Margaret Thatcher became the first female prime minister of the United Kingdom.

An all-female Japanese team reached the summit of Manaslu in the Himalayas, becoming the first women to climb a peak higher than 8,000 metres (26,247 ft) above sea level.

World War II: Aircraft from Imperial Japanese Navy vessels attacked Allied naval forces, beginning the Battle of the Coral Sea, the first naval action in which the participating ships never sighted or fired directly at each other.

During a labor rally in Chicago, a bomb explosion and gunfire led to the deaths of eight police officers and four members of the public.

The Boydell Shakespeare Gallery, part of a cultural project initiated by engraver John Boydell, opened in London.

American Revolution: The Colony of Rhode Island and Providence Plantations became the first of the Thirteen Colonies to renounce its allegiance to the British Crown.

Trunajaya rebellion: Dutch East India Company forces under Cornelis Speelman began an attack on Surabaya, on the island of Java.

Pope Alexander VI (pictured) issued the papal bull Inter caetera, establishing a line of demarcation dividing the New World between Spain and Portugal.