The Germans declared the area to be the "First Resettlement Area" of the General Gouvernement in November, 1942, which resulted in the "ethnic cleansing" of hundreds of villages in the region, to make room for German nationals. Tens of thousands of Poles were deported to labor or extermination camps, or killed outright, while others were singled out to be "Germanized" and resettled in the Reich.
Liberation came when the Red Army arrived in July 1944.
JOHN DAMSKI: Himmler once visited Zamosc, and finding that it was a lovely town--built on the model of Padua, Italy--he had the idea to turn it into a German city, called Himmlerstadt. However, if it was to be a German city he would need to get rid of all the Poles living there. To accomplish this he sent out a special commission to examine the population to decide who was German. Those with blue eyes--to the right; the others--out. I wasn't in front of that commission because I had left Zamosc by that time, but my brother Zygmunt, who was blond with blue eyes, was living there. The Germans measured his hands, and the length of his fingers--and these were supposedly educated people.