February 28 » Queen Ranavalona III, the last monarch of Madagascar, is deposed by a French military force.
April 30 » J. J. Thomson of the Cavendish Laboratory announces his discovery of the electron as a subatomic particle, over 1,800 times smaller than a proton (in the atomic nucleus), at a lecture at the Royal Institution in London.
July 11 » Salomon August Andrée leaves Spitsbergen to attempt to reach the North Pole by balloon. He later crashes and dies.
August 21 » Oldsmobile, an American automobile manufacturer and marque, is founded.
August 31 » Thomas Edison patents the Kinetoscope, the first movie projector.
September 10 » Lattimer massacre: A sheriff's posse kills 19 unarmed striking immigrant miners in Lattimer, Pennsylvania, United States.
Day of marriage March 18, 1921
The temperature on March 18, 1921 was between 2.4 °C and 10.6 °C and averaged 6.4 °C. There was 0.2 mm of rain. There was 3.6 hours of sunshine (30%). The average windspeed was 4 Bft (moderate breeze) and was prevailing from the southwest. Source: KNMI
In The Netherlands , there was from September 9, 1918 to September 18, 1922 the cabinet Ruys de Beerenbrouck I, with Jonkheer mr. Ch.J.M. Ruys de Beerenbrouck (RKSP) as prime minister.
February 27 » The International Working Union of Socialist Parties is founded in Vienna.
March 15 » Talaat Pasha, former Grand Vizir of the Ottoman Empire and chief architect of the Armenian Genocide is assassinated in Berlin by a 23-year-old Armenian, Soghomon Tehlirian.
March 18 » The second Peace of Riga is signed between Poland and the Soviet Union.
June 28 » Serbian King Alexander I proclaims the new constitution of the Kingdom of Serbs, Croats and Slovenes, known thereafter as the Vidovdan Constitution.
September 5 » Roscoe "Fatty" Arbuckle party in San Francisco ends with the death of the young actress Virginia Rappe: One of the first scandals of the Hollywood community.
October 8 » KDKA in Pittsburgh's Forbes Field conducts the first live broadcast of a football game.
When copying data from this family tree, please include a reference to the origin: Gert Jonker, "Family tree Jonker", database, Genealogy Online (https://www.genealogieonline.nl/jonker_stamboom/I25445.php : accessed February 17, 2026), "Aartje Knoppert (1897-????)".
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