Greater Poland uprising (1918–1919)

Military insurrection in German-occupied Greater Poland Greater Poland uprisingPart of the aftermath of World War I and Revolutions of 1917–1923Polish soldiers in trenches on the Polish–German front, January 1919Date27 December 1918 – 28 June 1919(6 months and 1 day)LocationGreater Poland regionResult Polish victoryTerritorialchanges Per the Treaty of Versailles, most of the Prussian provinces of Posen and West Prussia, the eastern part of Upper Silesia, and the area of Działdowo were annexed from Germany to Poland.Belligerents Polish Fighters Supported by: Poland GermanyCommanders and leaders Stanisław Taczak Józef Dowbor-Muśnicki Friedrich PolachUnits involved People's Guard P.M.O Greater Poland Army Imperial German Army Freikorps Strength Before the uprising: 10,000Beginning of January 1919: 27,000End of the uprising: 100,000 Beginning of the uprising: 2,500–4,500 End of the uprising: 20,000–30,000Casualties and losses ~2,000 killed6,000 wounded unknown Territorial evolution of Polandin the 20th century Pre-World War II Revolution in Congress Poland (1905–1907) Ostrowiec Republic Zagłębie Republic Separation of Kholm Governorate from Congress Poland and annexat