Polish Independence Day is celebrated annually on November 11th to commemorate Poland regaining sovereignty in 1918 after 123 years of partition among Russia, Prussia, and Austria. The holiday marks Poland reestablishing independence after World War I and the defeat of occupying forces, when Józef Pilsudski assumed leadership and began building Poland as a nation with its own military and government. November 11th has been a national holiday celebrating Polish independence since 1919.