As Haren lay in the occupation zone administered by the Polish I Corps (and more specifically the Polish 1st Armoured Division), it was chosen as the most appropriate centre of a Polish enclave in Germany.
Kuna Haren asus okupatsioonitsoonis, mida haldas Poola I korpus (ja täpsemalt Poola 1. soomusdiviis), valiti see, kui kõige sobivam Poola enklaavi keskus Saksamaal.