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The German Society for Celtic Studies (Deutsche Gesellschaft für keltische StudienDGKS) was a German institute founded in December 1936 for the research of Celtic studies.
After the start of World War II some members of the DGKS were assigned special tasks in the Abwehr and the Foreign Office, particularly in the Benelux countries, and in northern France. In the course of its existence, the cooperation between the DGKS and Ahnenerbe became ever closer. One of the central figures was Ludwig Mühlhausen [de] (1888-1956), who was a specialist in Welsh, had been honorary professor of Celtic Studies at the University of Hamburg from 1928-1936, was a Nazi party member and lead the politicization of Celtic studies in Germany after taking the Berlin Chair position for Celtic studies after Julius Pokorny was expelled for his Jewish ancestry. Mühlhausen from the beginning of 1940 also worked with Leo Weisgerber for foreign broadcasting propaganda. At a Celtic congress in Wernigerode at the beginning of September 1941, Mühlhausen spoke in favor of the continuation and "use of humanities in war". In June 1942, Mühlhausen was leader of an "education and research center for Celtic people research" newly established in the Ahnenerbe.
While working in collaboration with the SS-Ahnenerbe the DGKS was involved in espionage, as well as sabotage and encouraging Celtic ethnic minorities towards insurrection in Brittany and the British Isles.
Bauersfeld, Helmut (1937). Die Entwicklung der keltischen Studien in Deutschland. Schriftenreihe der "Deutschen Gesellschaft für keltische Studien". Heft 1 [The development of Celtic studies in Germany. Series of publications of the "German Society for Celtic Studies". Booklet 1] (in German). Berlin: Deutsche Gesellschaft für keltische Studien.
Boberach, Heinz (1984). Meldungen aus dem Reich. Die geheimen Lageberichte des Sicherheitsdienstes der SS, Volume II [Messages from the realm. The secret situation reports of the security service of the SS, Volume II] (in German). Herrsching. p. 917.{{cite book}}: CS1 maint: location missing publisher (link)
Hausmann, Frank-Rutger; Müller-Luckner, Elisabeth (2002). Die Rolle der Geisteswissenschaften im Dritten Reich [The role of the humanities in the Third Reich] (in German). Oldenburg: Oldenbourg Wissenschaftsverlag [de]. p. 149.