Schimana was born in Troppau (Opava). Troppau was at that time a part of Austria-Hungary. He the son of a newspaper editor. In 1915, he entered the Prague cadets school, from which he graduated in December 1918. In 1920, he left the Austrian army with the rank of lieutenant, and was subsequently employed as a librarian and bank clerk.
Schimana became an early member of the Nazi Party, on 7 December 1926 (Party-Nr. 49042), and joined the paramilitary SA in Munich. After the Nazis came to power, in 1934 he entered the uniformed Protection Police (Schutzpolizei) with the rank of Captain. In 1936 he was transferred to the Gendarmerie as Major. After the Anschluss, he was transferred to the Police Headquarters at Vienna as Commander of the motorized Gendarmerie for Austria. On 15 August 1939 entered the SS with the rank of Standartenführer. At the outbreak of the war he took over command of a field gendarmerie battalion in Poland, France then Generalgouvernement of Poland up to 1940. He held command of various schools of the motorized gendarmerie then staff duties into Main Office for Uniformed Police Hauptamt Ordnungspolizei from 1940 to 1941.
On 4 September 1941, he was appointed SS and Police Leader (SSPF) for the Saratov area, and later attached to the staff of the Higher SS and Police Leader (HSSPF) for Central Russia until July 1942, taking part in anti-partisan operations. From 21 July 1942 to 15 July 1943 he was SSPF of Belarussia, with headquarters at Minsk. Subsequently he underwent training as a divisional commander and was commander of the newly formed 14th "Galizien" SS Volunteers Division until October 1943. On 18 October, he was appointed HSSPF for Greece, in replacement to Jürgen Stroop, a position he held until the withdrawal of German forces from the country in September–October 1944. He became actively engaged in carrying out the persecution of Greek Jews and the campaign against the Greek Resistance movement. In this capacity he was instrumental in the formation of the infamous Security Battalions. After the German withdrawal, he was appointed HSSPF of the Danube Sector, with headquarters at Vienna, in which position he remained until the German capitulation.
He was captured by the Allies and imprisoned, but committed suicide before he could be brought to trial.