From 1900 to 1924, except for the war years of 1914 to 1918, he worked as an "administrative official" in the city government of Munich.[1] During World War I, Schwarz served as a second lieutenant in the German Army.[2] Due to gastric troubles which afflicted him for his entire life (he was considered 30 percent disabled in that war), he was spared field duty beginning in 1916.