Prior to joining the SS he was a Hauptmann (Captain) in the Heer (German Army), being awarded the Iron Cross I & II class, the Eastern Front Medal for service on the Eastern Front during the first Russian winter of the war 1941/42, and the German Cross as the commander of a Sturmgeschütz (Assault Gun StuG) Battalion.
Hugo Primozic (16 February 1914 – 18 March 1996) was one of Germany's Sturmgeschütz (assault gun) aces during World War II and was noted for his quick reactions, clever tactical use of ground and the icy nerve which in tense situations enabled him to hold his fire until his opponent had closed to point-blank range.
he gathered two hastily repaired Sturmgeschütz and 25 Grenadiers and launched a counterattack which resulted in the destruction of three T-34 tanks, fifteen anti-tank guns and taking 200 prisoners.
On 1 November 1941, Wendorff was sent to the SS Junkerschule in Bad Tölz and returned to the Sturmgeschütz battalion in April 1942, as an Untersturmführer (Second Lieutenant).