Suharto resigns, after 32 years as President of Indonesia and his 7th consecutive re-election by the Indonesian Parliament (MPR). Suharto's hand-picked Vice President, B. J. Habibie, becomes Indonesia's third president.
Mikhail Gorbachev arrives in Ottawa for a 29-hour visit.
Cold War: The leaders of the Yemen Arab Republic and the People's Democratic Republic of Yemen announce the unification of their countries as the Republic of Yemen.
The Ninth Street Show, otherwise known as the 9th Street Art Exhibition, a gathering of a number of notable artists, marks the stepping-out of the post war New York avant-garde, collectively known as the New York School.
The Russian Empire commits the Circassian Genocide. More than 1.5 Million Circassians are murdered and surviving Circassians were driven from their homeland to the Ottoman Empire, ending the Russian-Circassian War.
Battle of Aspern-Essling: Austrian troops under Archduke Karl beat the French under Napoleon in a hard fought battle.
Tuesday, May 21, 1799
Siege of Acre ends after two months: Napoleon's attempt to widen his Middle Eastern caign into Syria is frustrated by Ottoman forces, and he withdraws to Egypt.
Monday, May 21, 1792
An old lava dome collapses in Kyūshū, Japan when Mount Unzen volcano erupts the resulting avalanche and tsunami kills about 14,300 people.
Sunday, May 21, 1786
The trial of the Necklace Affair ends in Paris.
Sunday, May 21, 1758
Seven Years' War ndash French and Indian War: Mary Cbell is abducted from her home in Pennsylvania by Lenape.
Treaty of Troyes: With the Burgundian faction dominant in France, King Charles VI of France acknowledges Henry V of England as his heir and as virtual ruler of most of France.
Friday, May 14, 1260 (Julianian calendar)
Kublai sends his envoy Hao Jing to negotiate with Song Dynasty Chancellor Jia Sidao, after the small force left by Kublai south of the Yangzi River is destroyed by a Chinese army of the Southern Song Dynasty. Chancellor Jia Sidao imprisons the entire embassy of Kublai. This slight will not be forgotten by Kublai, but he is unable to assault the Song due to the civil war with his rival brother Ariq Böke.