February 27 » The British Labour Party is founded.
April 5 » Archaeologists in Knossos, Crete, discover a large cache of clay tablets with hieroglyphic writing in a script they call Linear B.
May 18 » The United Kingdom proclaims a protectorate over Tonga.
June 17 » Boxer Rebellion: Western Allied and Japanese forces capture the Taku Forts in Tianjin, China.
June 21 » Boxer Rebellion. China formally declares war on the United States, Britain, Germany, France and Japan, as an edict issued from the Empress Dowager Cixi.
December 14 » Quantum mechanics: Max Planck presents a theoretical derivation of his black-body radiation law.
Day of marriage May 20, 1926
The temperature on May 20, 1926 was between 5.7 °C and 17.6 °C and averaged 12.1 °C. There was 3.9 hours of sunshine (25%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the south-southeast. Source: KNMI
January 8 » Crown Prince Nguyễn Phúc Vĩnh Thuỵ ascends the throne to become the last monarch of Vietnam.
April 24 » The Treaty of Berlin is signed. Germany and the Soviet Union each pledge neutrality in the event of an attack on the other by a third party for the next five years.
May 18 » Evangelist Aimee Semple McPherson disappears in Venice, California.
May 25 » Sholom Schwartzbard assassinates Symon Petliura, the head of the government of the Ukrainian People's Republic, which is in government-in-exile in Paris.
August 6 » Gertrude Ederle becomes the first woman to swim across the English Channel.
August 6 » In New York City, the Warner Bros.' Vitaphone system premieres with the movie Don Juan starring John Barrymore.
Day of death January 20, 1981
The temperature on January 20, 1981 was between -1.1 °C and 2.8 °C and averaged 0.6 °C. There was 1.2 mm of rain during 0.9 hours. There was 1.9 hours of sunshine (22%). The partly clouded was. The average windspeed was 2 Bft (weak wind) and was prevailing from the north. Source: KNMI
In The Netherlands , there was from Monday, December 19, 1977 to Friday, September 11, 1981 the cabinet Van Agt I, with Mr. A.A.M. van Agt (CDA/KVP) as prime minister.
In The Netherlands , there was from Friday, September 11, 1981 to Saturday, May 29, 1982 the cabinet Van Agt II, with Mr. A.A.M. van Agt (CDA) as prime minister.
March 1 » Provisional Irish Republican Army member Bobby Sands begins his hunger strike in HM Prison Maze.
March 30 » U.S. President Ronald Reagan is shot in the chest outside a Washington, D.C., hotel by John Hinckley, Jr.; three others are wounded in the same incident.
May 21 » The Italian government releases the membership list of Propaganda Due, an illegal pseudo-Masonic lodge that was implicated in numerous Italian crimes and mysteries.
May 21 » Transamerica Corporation agrees to sell United Artists to Metro-Goldwyn-Mayer for $380million after the box office failure of the 1980 film Heaven's Gate.
July 29 » A worldwide television audience of over 700million people watch the wedding of Charles, Prince of Wales, and Lady Diana Spencer at St Paul's Cathedral in London.
September 3 » The Convention on the Elimination of All Forms of Discrimination Against Women, an international bill of rights for women, is instituted by the United Nations.
When copying data from this family tree, please include a reference to the origin: Hans Weening, "Family tree Weening", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-weening/I113512.php : accessed October 25, 2026), "Klaas Jan Boersma (1900-1981)".
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