Justin K. Thannhauser was an art dealer active in Munich, Berlin, Lucerne and Paris. He was the son of Heinrich Thannhauser [1859-1935], who established the family gallery in the spring of 1909 in the Arco Palais on Theatinerstrasse in Munich. Heinrich had been an associate of F.J. Brakl in Munich from 1906. The first exhibitions in Munich were of the impressionist painters, followed by exhibitions including modern artists such as Kandinsky, Braque, Picasso, Roualt, and Vlaminck. During the first world war, the gallery was forced to curtail its activities significantly. After the war, the leadership of the gallery was assumed by Justin Thannhauser. A branch was opened in Lucerne (1919-1937) and later Berlin (1927-1937). The original gallery in Munich remained open until 1928. In 1937, Justin Thannhauser was forced to leave Germany; he established the gallery in Paris later that same year. He remained in Paris until August 1939 and went to Swtizerland; in 1941 he came to New York. Justin Thannhauser had two sons with his first wife Kate [1894-1960], both of whom predeceased him: Heinz [1918-1944] and Michael [1920-1952]. Justin and his second wife Hilde moved to Bern in 1971, where he died in 1976. A portion of Justin Thannhauser's art collection is now in the Guggenheim Museum in New York City.
Katalog der Modernen Galerie Heinrich Thannhauser, München. Munich, 1916
Barnett, Vivian Endicott. The Guggenheim Museum Justin K. Thannhauser Collection. New York, 1978:13-15