January 23 » The Malolos Constitution is inaugurated, establishing the First Philippine Republic. Emilio Aguinaldo is sworn in as its first President.
March 30 » German Society of Chemistry issues an invitation to other national scientific organizations to appoint delegates to the International Committee on Atomic Weights.
May 30 » Pearl Hart, a female outlaw of the Old West, robs a stage coach 30 miles southeast of Globe, Arizona.
June 7 » American Temperance crusader Carrie Nation begins her campaign of vandalizing alcohol-serving establishments by destroying the inventory in a saloon in Kiowa, Kansas.
July 17 » NEC Corporation is organized as the first Japanese joint venture with foreign capital.
September 13 » Mackinder, Ollier and Brocherel make the first ascent of Batian (5,199 m - 17,058ft), the highest peak of Mount Kenya.
Day of marriage March 19, 1921
The temperature on March 19, 1921 was between 0.5 °C and 10.6 °C and averaged 5.6 °C. There was 0.7 mm of rain. There was 8.4 hours of sunshine (70%). 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 21 » Rezā Shāh takes control of Tehran during a successful coup.
March 17 » The Second Polish Republic adopts the March Constitution.
March 21 » The New Economic Policy is implemented by the Bolshevik Party in response to the economic failure as a result of war communism.
August 3 » Major League Baseball Commissioner Kenesaw Mountain Landis confirms the ban of the eight Chicago Black Sox, the day after they were acquitted by a Chicago court.
October 29 » United States: Second trial of Sacco and Vanzetti in Boston, Massachusetts.
December 22 » Opening of Visva-Bharati College, also known as Santiniketan College, now Visva Bharati University, India.
When copying data from this family tree, please include a reference to the origin: Jan Kaper, "Family tree Kaper", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-kaper/I62702.php : accessed February 25, 2026), "Popke van der Werf (1899-????)".
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