Reserve Police Battalion 101 was a Nazi German paramilitary formation of '' Ordnungspolizei '' ( Order Police , abbreviated as Orpo ) , operating under the control of the SS . Formed in Hamburg , it was deployed in September 1939 along with the Wehrmacht army in the invasion of Poland . Initially , the Police Battalion 101 ( ) guarded Polish prisoners of war behind German lines , and carried out expulsion of Poles , called " resettlement actions " , in the new '' Warthegau '' territory around Poznań and Łódź . Following the personnel change and retraining from May 1941 until June 1942 , it became a major perpetrator of the Holocaust in occupied Poland
expulsion of Poles
Expulsion of Poles by Nazi Germany
Reserve Police Battalion 101