1974 – In an informal article in a medical journal, Henry Heimlich introduced the concept of abdominal thrusts, commonly known as the Heimlich maneuver, to treat choking victims.
1844 – The last known pair of great auks(one pictured), the only modern species in the genus Pinguinus of flightless birds, were killed on Eldey, Iceland.
1976 – The Teton Dam in eastern Idaho, U.S., collapsed as its reservoir was being filled for the first time, resulting in the deaths of eleven people and 13,000 cattle, and causing up to $2 billion in damage.
1832 – The Reform Act, which is widely credited with launching modern democracy in the United Kingdom, received royal assent.
1892 – Homer Plessy, a mixed-race man from New Orleans, was arrested for refusing to leave his seat in the "whites-only" car of a train; he lost the resulting court case, Plessy v. Ferguson.
2009 – Two American journalists, having been arrested for illegal entry into North Korea, were sentenced to twelve years hard labor before being pardoned two months later.
1646 – Franco-Spanish War: French and Spanish fleets fought the inconclusive Battle of Orbetello, with sailing vessels of both sides having to be towed into action by galleys due to light winds.
1374 – An outbreak of dancing mania, in which crowds of people danced themselves to exhaustion, began in Aachen (in present-day Germany) before spreading to other parts of Europe.
1939 – The first of the Thai cultural mandates was issued, officially changing the country's name from Siam to Thailand.
1409 – The Council of Pisa elected Peter of Candia as Pope Alexander V(pictured), becoming the third simultaneous claimant of the title of leader of the Roman Catholic Church.
1889 – Bangui, the capital and largest city of the present-day Central African Republic, was founded in French Congo.
1613 – The original Globe Theatre in London burned to the ground after a cannon employed for special effects misfired during a performance of Henry VIII and ignited the roof.