Events, birthdays and anniversaries for 20 May
1498: Vasco da Gama arrived at Calicut, southern India, after discovering a route via the tip of southern Africa.
1588: The Spanish Armada set sail from Lisbon on a mission to invade England. It comprised 129 ships sent by Phillip II of Spain. 1840: York Minster was badly damaged by fire.
1873: Levi Strauss and Jacob Davis received a United States patent for blue jeans with copper rivets.
1883: Krakatoa begins to erupt. The volcano’s final and most notable explosion occurred on 26 August.
1902: Cuba gains independence from the United States. Tomás Estrada Palma became the first president of Cuba.
1932: Amelia Earhart became the first woman to make a solo air crossing of the Atlantic.
1940: The first prisoners arrived at a new concentration camp at Auschwitz.
1941: Germany began an aerial invasion of Crete.
1956: The Americans dropped their first hydrogen bomb over Bikini atoll in the Marshall Islands of the Pacific.
1965: PIA Flight 705, a Pakistan International Airlines Boeing 720-040 B, crashed while descending to land at Cairo International Airport, killing 119 of the 125 passengers and crew.
1969: The Battle of Hamburger Hill in Vietnam ended.
1983: First publications of the discovery of the HIV virus that causes Aids in the journal Science by Luc Montagnier and Robert Gallo individually.
1990: An Israeli gunman killed seven Arab workers, setting off serious riots in the occupied territories in which seven more Arabs died as Israeli troops were called in.
1991: The USSR passed a law allowing Soviet citizens to leave the country of their own free will.
1993: The House of Commons gave the Maastricht Treaty bill its third reading. Forty-one Conservative MPs voted against the agreement.
1994: Cluny Parish Church in Edinburgh was packed and 2,000 people stood in the streets outside for the funeral service of the Labour leader, John Smith.
2002: The independence of East Timor was recognised by Portugal, formally ending 23 years of Indonesian rule and three years of provisional United Nations administration.
2009: An Indonesian military transport plane carrying troops and their families crashed on the island of Java, killing more than 100 people.
2010: The first annual Everybody Draw Muhammad Day was celebrated. The event caused Pakistan to shut down the social networking site Facebook in protest.
Cher (Cherilyn Sarkasian), actress and singer, 67; Colin John MacLean Sutherland, Lord Carloway, Senator of the College of Justice in Scotland, 59; Joe Cocker OBE, singer, 69; Lynn Davies CBE, Olympic gold medallist long-jumper, 71; Greg Dyke, director-general, BBC 2000-4, 66; Mark McGhee, football manager, 56; Michèle Roberts, novelist, 64; Earl Spencer, 49.
Births: 1799 Honoré de Balzac, French novelist; 1806 John Stuart Mill, philosopher and economist; 1895 Reginald Joseph Mitchell, aircraft designer, including Second World War fighter Spitfire; 1920 Betty Driver MBE, actress (Coronation Street).
Deaths: 1506 Christopher Columbus, navigator and discoverer of the New World; 1864 John Clare, peasant poet (died in lunatic asylum); 1975 Dame Barbara Hepworth, sculptor.