Gedvilas served as Chairman of the Council of People's Commissars of Lithuania (in 1946 renamed to the Council of Ministers) from August 25, 1940, to January 16, 1956 (position equivalent to Prime Minister). In this capacity he supervised Sovietization of Lithuania and signed off on persecution orders, including the mass deportation of Lithuanians into Gulags and other forced settlements. In 1944, he led a delegation that signed an agreement with the Polish Committee of National Liberation that led to the repatriation of Poles.