Fritz Boehmer: A Painter Caught Between Expressionism and Political Engagement Fritz Boehmer (1875 - 1942) was a German lieutenant colonel on the General Staff and one of the 20 July Plotters. He belonged to Infantry Regiment 9 (I.R. 9) from Potsdam, from which also came many of the other plotters. They served, among others, Major General Henning von Tresckow and Fritz-Dietlof von der Schulenburg in the regiment. Altogether, I.R. 9 su…