During the German occupation of Paris in 1940, von Behr played a major role in looting art from Jews.
As deputy to the staff leader Gerhard Utikal,[2][3] von Behr headed the Einsatzstab Reichsleiter Rosenberg (ERR),[4] West Department in Paris.
"[11][12] Along with Bruno Lohse, von Behr was considered one of the "masterminds of the artistic plunder enacted by the ERR in France.
"[13] After the arrival of Allied troops, von Behr and his wife committed suicide, with hydrogen cyanide on 19 April 1945.
[14] In von Behr's residence, Schloss Banz, the US armed forces found not only large holdings of books looted from Western and Eastern European libraries, but also ERR archive files that had been relocated there, which provided the basis of the Nuremberg trial against Alfred Rosenberg.