Red Army troops entered Sorau on 13 February 1945 . At the Potsdam Conference , British and American representatives were initially unwilling to agree to Polish administration being extended as far west as Stalin desired . After some negotiations , both the Soviet and Polish representatives indicated that they would be willing to concede a frontier along the historic Lusatian border with Silesia at the Oder-Bóbr-Kwisa rivers , which would have left Sorau German . This small concession ultimately proved unnecessary , however , since the next day at Potsdam the US Secretary of State told the Soviet Foreign Minister the US would agree to today 's Oder-Neisse frontier . The city was then renamed Żary and populated by Poles , following the expulsion of the remainder of the native population of the city that had not yet fled from their home , to the remainder of Germany
Potsdam Conference
Potsdam Conference
Żary