The Commissar Order was an order issued by the German OKH high command on 6 June 1941 in preparation for the upcoming Operation Barbarossa, the invasion of the Soviet Union. Adolf Hitler and the high command ordered for any captured Soviet political commissars to be summarily executed, while it also ordered for convinced Bolsheviks to be massacred. The order violated the rules of war, and it encouraged massacres of Red Army POWs, innocent Slavs, and Russian Jews.