1915. Up until then, it was one of the few cities whose Polish name was retained during German rule. In 1904 the "Sokół" Polish Gymnastic Society in Zabrze was established, which was also a Polish patriotic and pro-independence organization. As a result of the Prussian harassment it was liquidated in 1911, but it was reactivated twice, in 1913 and 1918. Its members took an active part in the post-war plebiscite campaign and the Silesian uprisings. Interwar period During the plebiscite held after World War I, 21,333 inhabitants (59%) of the Hindenburg commune voted to remain in Germany, while 14,873 (41%) voted for incorporation to Poland, which just regained its independence. In May 1921 the Third Silesian Uprising broke out and Hindenburg was captured by Polish insurgents, who held it until the end of the uprising. When Upper Silesia was divided between Poland and Germany in 1921, the Hindenburg commune remained in Germany, while the present-day districts of Kończyce, Makoszowy and Pawłów were reintegrated with Poland. It received its city charter in 1922. Just five years after receiving city rights Hindenburg became the biggest city in German-ruled western Upper Silesia and the second biggest city in German-ruled Silesia after Wrocław (then Breslau). Nevertheless, various Polish organizations still operated in the city in the interbellum, including a local branch of the Union of Poles in Germany, Polish libraries, sports clubs, credit unions, choirs, scout troops and an amateur theater. Polish newspaper Głos Ludu was published in the city. In a secret Sicherheitsdienst report from 1934, Zabrze was named one of the main centers of the Polish movement in western Upper Silesia. In terms of religion, most of the city's population adhered to the Catholic Church. In the 1920s, the communists, Christian democrats and nationalists enjoyed the greatest support among the German population, while Poles supported Polish parties. In 1928, among the largest cities in western Upper Silesia, Polish parties received the most votes in Zabrze. In the March 1933 elections, most of the citizens voted for the Nazi Party, followed by Zentrum and the Communist Party. Nazi politician Max Fillusch became the city's mayor and remained in the position until 1945. The anti-Polish organization Bund Deutscher Osten was very active in the city, it dealt with propaganda, indoctrination and espionage of the Polish community, as well as denouncing Poles to local authorities. When, the Barbórka (traditional holiday of miners) church services were