The temperature on May 18, 1921 was between 10.5 °C and 18.2 °C and averaged 13.2 °C. There was 0.2 mm of rain. There was 5.0 hours of sunshine (32%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the north. 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.
March 20 » The Upper Silesia plebiscite was a plebiscite mandated by the Versailles Treaty to determine a section of the border between Weimar Germany and Poland.
June 28 » Serbian King Alexander I proclaims the new constitution of the Kingdom of Serbs, Croats and Slovenes, known thereafter as the Vidovdan Constitution.
July 22 » Rif War: The Spanish Army suffers its worst military defeat in modern times to the Berbers of the Rif region of Spanish Morocco.
July 27 » Researchers at the University of Toronto, led by biochemist Frederick Banting, prove that the hormone insulin regulates blood sugar.
July 29 » Adolf Hitler becomes leader of the National Socialist German Workers Party.
October 29 » The Harvard University football team loses to Centre College, ending a 25-game winning streak. This is considered one of the biggest upsets in college football.
When copying data from this family tree, please include a reference to the origin: Peter Menting, "Family tree Menting", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-menting/I29980.php : accessed February 23, 2026), "Johannes Bertisen (± 1897-????)".
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