After the German–Soviet non-aggression treaty of August 1939, the ideological antagonism between the Nazis and the Communists was temporarily mollified. The SS knew that Communists were able to organize people and that they had an international network, which, from the point of view of the concentration camp direction, was useful because after the start of the war, Buchenwald had a multilingual prisoner population. When Germany later invaded the Soviet Union in 1941, the Communist prisoners at first lost these positions, but later managed to win them back. To strengthen camp cohesion, the Communist kapos made sure that prisoner functionaries were from every country. They also worked with Social Democrats and middle class politicians to set up the People's Front policy of the Comintern.