1) Slavic ethnic group 
Ruhrpolen (`Ruhr Poles”) is a German umbrella term for Poles (including Silesians, Masurians, Kashubians), who migrated to the rapidly industrializing areas of the Ruhr Valley. ==Origins== The immigrants mainly came from what were then eastern territories of Germany (Province of Posen, East Prussia and West Prussia, Province of Silesia), which.....