From 1942 Crüger was able to be open about his membership of the Communist Party of Germany and 1943 he took on responsibility for publishing a Swiss version of the journal of the Moscow backed Movement for a Free Germany ("Bewegung Freies Deutschland"). During 1944 and 1945 he actively built up support for the Free Germany movement in Swiss labour camps, and held a position as Swiss Secretary for the movement till it was dissolved at the end of 1945. By that time war had ended, formally in May 1945, leaving the western two thirds of Germany divided into four military occupation zones. In January 1946 Herbert Crüger returned to Germany, settling not in his former home city of Berlin, but in the US occupation zone, further to the west. Between 1946 and 1948 he served as a senior official ("Regierungsrat") with responsibilities covering youth welfare in the Ministry for Labour and welfare in the newly relaunched regional state of Hesse. His position became anomalous after regional elections were held in December 1946 in which the Communist Party performed badly and following which they accordingly withdrew from the collaborative arrangements with the regional SPD which had till that point been in place. It was more than a year later before the party instructed Crüger to resign from his government post, which he did on 31 January 1948.