The UK's health minister, R. H. Turton, rejects a proposed government campaign against smoking, on the grounds that the theory that smoking causes lung cancer "has not been proved".[12]
British coaster Fred Everard collides with another British ship, SS Walstream off Margate, Kent. Fred Everard sinks with the loss of one crew member.[19]
US steam schoonerHoward Olson collides with another US ship, SS Marine Leopard, 175 nautical miles (324 km) south of San Francisco, California. The Howard Olson sinks, with the loss of six members of her 28 crew.[26][27]
Harry Pollitt resigns as General Secretary of the British Communist Party; Pollitt was suffering from poor health, and was replaced by John Gollan.[28]
Six business executives from a firm in Chicago, United States, are killed, along with two crew members, when their company plane crashes near Jeffersonville, Indiana.[31]
Fighting breaks out between French troops and Algerian independence fighters, continuing until 22 May. At the end of the encounter, 24 French soldiers and 67 Algerian rebels are dead.[33]
Born:Mirek Topolánek, Czech politician (Prime Minister 2006–2009), in Vsetin
In the United States, NBC's peacock logo is used for the first time, to indicate the quality of its colour television broadcasting.[39]
Swedish teacher Gunnel Gummeson and her American boyfriend Peter Winant are reportedly seen for the last time in Shibarghan, Afghanistan, before going missing. In 1977, Gummeson is declared presumed dead, probably murdered.[40]
A Gloster Meteor NF.Mk 11 overshoots the runway while taking off from RAF Wahn, West Germany. The two-man crew were unhurt, but the plane was damaged beyond repair.[45]
Dutch coaster Prins Bernhard, collides with the West German ship SS Tanger off Folkestone, Kent, and sinks. All on board are rescued by the Dover lifeboat.[47]
The Hong Kong-registered tanker Lucky Carrier, on a voyage from Chalna to Akyab, runs aground at Fakir Point, Burma. The ship was later towed to Singapore where she would be declared a constructive total loss and scrapped.[48]
^Katz, Ephraim (1979). The Film Encyclopedia: The Most Comprehensive Encyclopedia of World Cinema in a Single Volume. Perigee Books. ISBN0-399-50601-2. P. 195
^"Orléans Aviation Disaster Memorial". National Inventory of Canadian Military Memorials. Canadian Department of National Defence. 2008-04-16. Archived from the original on 2014-05-20. Retrieved 20 May 2014.
^"Gaul Vencedor Del "Giro"" [Gaul the Winner of the "Tour"]. El Mundo Deportivo (in Spanish). 14 June 1956. p. 1. Archived from the original on 17 October 2013. Retrieved 27 May 2012.
^"Bird Like Flyer Plunges To Death". Associated Press. May 21, 1956. Retrieved October 16, 2012 – via Google News. Leo Valentin, the Frenchman who tried to fly like a bird, was killed today trying to glide from a plane at 9,000 feet. ...