In October 1944 the Germans troops and administrators were ejected from Serbia by a potent - if slightly implausible - de facto alliance between Yugoslav Partisans and the Soviet army. By December 1944 Sattler had made his way to Vienna where between 18 December and 9 May 1945 he was involved in the so-called "Hungarian Repatriation" ("ungarische Rückführungsaktion") operation. During the winter of 1944/45 he was one of those responsible for eliminating the few surviving Jews in the Hungarian concentration camps. 9 May 1945 was a significant date because it was the date on which, for records produced with reference to Moscow time, the war ended in German defeat. (The countryside around Vienna and much of the city itself was already under Soviet military occupation.)