Born in Graz in 1905, relocated to Carinthia in 1908, studied at the Academy of Fine Arts in Vienna in 1925-1930 with Delug and Bacher.
Thereafter secondary school teacher in Vienna, 1935-1938 worked as a painter in Klagenfurt and Munich, 1939-1942 again teaching in Vienna, 1942 military service, 1943-1946 prisoner of war in the United States.
From 1946 until his death in 1993 Karl Bauer lived as a freelance painter in Klagenfurt.
His favorite motifs were, in addition to the Carinthian landscape, portraits, groups of people and religious themes. The content was given less importance than the composition and the colors. The influences that are evident in him, ranging from the classics of Modernism (in Carinthia primarily the early Boeckl, in Munich Hans von Marées) to art developments of the post-war period.