The Poles carried out two uprisings during the campaign, in August 1919 and August 1920. The Allies restored order in each case, but the Polish insurrectionists clashed with German "volunteers," the Freikorps.T. Hunt Tooley, "German Political Violence and the Border Plebiscite in Upper Silesia, 1919-1921," Central European History 21 (March 1988): 56-98.
