Born July 31, 1890; died Jan. 13, 1944, in Scheveningen, near The Hague. Figure in the Dutch labor movement.
Schalker joined the Social Democratic Labor Party in 1914 and the leftist Social Democratic Party in 1916; in 1918 he became a member of the Communist Party of the Netherlands (CPN). In 1925 he became a member of the Central Committee of the CPN. In 1929–30, Schalker was secretary of the district committee of the CPN in the province of South Holland, and in 1930 he became political secretary of the party’s Central Committee. From 1933 to 1937 he was a deputy to parliament. In 1935, at the Seventh Congress of the Comintern, he was elected a candidate member of the Comintern’s Executive Committee. In 1937 and 1938 he represented the CPN in the Comintern. In 1938 he became secretary of the Central Committee of the CPN.
In October 1943, after the occupation of the Netherlands by fascist German troops (May 1940), Schalker joined the illegal leadership of the CPN. He was seized by the Hitlerites in November 1943 and was subsequently shot.