The temperature on April 15, 1915 was between -1.8 °C and 13.1 °C and averaged 6.7 °C. There was 11.8 hours of sunshine (85%). The average windspeed was 2 Bft (weak wind) and was prevailing from the west. Source: KNMI
In The Netherlands , there was from August 29, 1913 to September 9, 1918 the cabinet Cort van der Linden, with Mr. P.W.A. Cort van der Linden (liberaal) as prime minister.
April 22 » The use of poison gas in World War I escalates when chlorine gas is released as a chemical weapon in the Second Battle of Ypres.
July 7 » Colombo Town Guard officer Henry Pedris is executed in British Ceylon for allegedly inciting persecution of Muslims.
July 7 » The First Battle of the Isonzo comes to an end.
July 16 » At Treasure Island on the Delaware River in the United States, the First Order of the Arrow ceremony takes place and the Order of the Arrow is founded to honor American Boy Scouts who best exemplify the Scout Oath and Law.
July 25 » RFC Captain Lanoe Hawker becomes the first British pursuit aviator to earn the Victoria Cross.
August 4 » World War I: The German 12th Army occupies Warsaw during the Gorlice–Tarnów Offensive and the Great Retreat of 1915.
Day of death February 12, 1920
The temperature on February 12, 1920 was between 1.4 °C and 8.5 °C and averaged 4.6 °C. There was 6.4 hours of sunshine (66%). The average windspeed was 4 Bft (moderate breeze) and was prevailing from the west. 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.
January 13 » The Reichstag Bloodbath of January 13, 1920, the bloodiest demonstration in German history.
February 10 » About 75% of the population in Zone I votes to join Denmark in the 1920 Schleswig plebiscites.
March 19 » The United States Senate rejects the Treaty of Versailles for the second time (the first time was on November 19, 1919).
July 20 » The Greek Army takes control of Silivri after Greece is awarded the city by the Paris Peace Conference; by 1923 Greece effectively lost control to the Turks.
August 11 » The Latvian–Soviet Peace Treaty, which relinquished Russia's authority and pretenses to Latvia, is signed, ending the Latvian War of Independence.
October 10 » The Carinthian plebiscite determines that the larger part of the Duchy of Carinthia should remain part of Austria.
When copying data from this family tree, please include a reference to the origin: J. van Broekhoven, "Database Van Broekhoven", database, Genealogy Online (https://www.genealogieonline.nl/database-van-broekhoven/I98775.php : accessed February 18, 2026), "Johannes Theodorus Opdam (1915-1920)".
Copy warning
Genealogical publications are copyright protected. Although data is often retrieved from public archives, the searching, interpreting, collecting, selecting and sorting of the data results in a unique product. Copyright protected work may not simply be copied or republished.
Please stick to the following rules
Request permission to copy data or at least inform the author, chances are that the author gives permission, often the contact also leads to more exchange of data.
Do not use this data until you have checked it, preferably at the source (the archives).
State from whom you have copied the data and ideally also his/her original source.