Ruhrpolen (ˈʁuːɐ̯ˌpoːlən, “Ruhr Poles”) is a German umbrella term for the Polish migrants and their descendants who lived in the Ruhr area in western Germany since the 19th century. The Poles (including Masurians, Kashubians, Silesians, and other groups) migrated to the rapidly industrializing region from Polish-speaking areas of the German Empire.
The immigrants mainly came from what was then eastern provinces of Germany (Province of Posen, East Prussia, West Prussia, Province of Silesia), which were acquired by the Kingdom of Prussia in the late-18th-century Partitions of Poland or earlier, and which housed a significant Polish-speaking population. This migration wave, known as the Ostflucht, began in the late 19th century, with most of the Ruhrpolen arriving around the 1870s. The migrants found employment in the mining, steel and construction industries. In 1913 there were between 300,000 and 350,000 Poles and 150,000 Masurians. Of those, one-third were born in the Ruhr area.
The Protestant Masurians did not accept being identified with Catholic Poles and underlined their loyalty to Prussia and the German Empire.
The first Polish organization Jedność was founded in 1876 in Dortmund by bookseller Hipolit Sibilski. In 1890, Wiarus Polski, the first Polish newspaper in the region, was established in Bochum. Various Polish organizations were founded in the region, including Towarzystwo św. Michała ("St. Michael's Club") in 1888, Związek Polaków w Niemczech ("League of Poles in Germany") in 1894, a regional branch of the "Sokół" Polish Gymnastic Society in 1898, and Zjednoczenie Zawodowe Polskie ("Polish Professional Union") in 1902. Dozens of Polish bookstores were founded in various places, including Dortmund, Bochum, Herne, Witten, Recklinghausen, Oberhausen, Habinghorst (present-day district of Castrop-Rauxel), Ückendorf (present-day district of Gelsenkirchen), Bruckhausen and Laar (present-day districts of Duisburg). There were also various Polish companies, co-operative shops, banks, sports clubs and singing clubs.