Karl Hermann Dietrich Lothar Erdmann (12 October 1888 – 18 September 1939) was a German journalist. During the Weimar Republic he was the editor of the trade union theory organ . He was a main supporter of the turning away of trade unions from social democracy at the end of the Republic. Despite his rapprochement with National Socialism, he died after maltreatment in the Sachsenhausen concentration camp.
