- 1241 – Mongol invasion of Poland: Mongols overwhelmed the Polish armies of Sandomierz and Kraków provinces in the Battle of Chmielnik and plundered the abandoned city of Kraków.
- 1913 – King George I of Greece (pictured) was assassinated in Thessaloniki by Alexandros Schinas, who had no apparent motive.
- 1925 – The Tri-State Tornado spawned in Missouri, traveled over 219 miles (352 km) across Illinois and Indiana, and killed 695 along the way, making it the tornado with the longest continuous track ever recorded in the world and the deadliest in U.S. history.
- 1970 – The National Assembly of Cambodia ousted Prince Norodom Sihanouk as head of state, and Prime Minister Lon Nol invoked emergency powers to take over.
- 1996 – The deadliest fire in Philippine history burned a nightclub in Quezon City, leaving 162 dead.