He continued his studies in philosophy, law, and economics until 1910 at various universities in Munich, Freiburg, Berlin and Heidelberg, but never graduated.
His daughter Gerda (also known as Greta) was married Alexander Catsch who worked at the Kaiser Wilhelm Institute in Buch; they were forced to go to the Soviet Union with other scientists for 5 years following World War II.
His son Karl-Heinz was imprisoned for several months on accusations of "decomposing military strength", later becoming editor-in-chief for multiple publications including BZ, Berliner Morgenpost, Bild-Zeitung, "Quick", and "Revue".
[citation needed] On 18 May 1942 Herbert Baum's resistance group carried out an arson attack on an anti-Soviet propaganda exhibition.
Half of these Jews were murdered at Sachsenhausen concentration camp on the same day, 28 May, including Hermann Hagen.
[3][4] The Nazi acts of revenge for these events culminated on 10 June that year with the destruction of the village of Lidice in the Protectorate of Bohemia and Moravia.
The plaque is built into the street on front of homes that were previously inhabited by primarily Jewish residents who were murdered in the Holocaust.