Prior to 1945 , Gubin was part of the historic town of Guben , which belonged to the Prussian Province of Brandenburg within the German Reich . When after World War II the Oder – Neisse line was chosen as the new German – Polish border at the Potsdam Conference , Guben was split between the two countries . The eastern portion of the devastated city , including the historic centre , became Polish Gubin , from which its remaining pre-war German population was expelled . They were replaced by Polish settlers from territories east of the Curzon Line
Potsdam Conference
Potsdam Conference
Gubin, Poland