As the commander of a battalion in an SS-V regiment, Gille participated in the invasion of Poland and in the western campaign. In 1940 he was appointed a regimental commander in the SS Division Wiking, led by Felix Steiner.
During World War II, Gille served as a battalion commander within an SS-V regiment. He took part in both the invasion of Poland and the Western Campaign. In 1940, he was promoted to regimental commander for the SS Division Wiking, under the command of Felix Steiner.