The Province of Brandenburg (German: Provinz Brandenburg) was a province of Prussia from 1815 to 1945. Brandenburg was established in 1815 from the Kingdom of Prussia's core territory, comprised the bulk of the historic Margraviate of Brandenburg (excluding Altmark) and the Lower Lusatia region, and became part of the German Empire in 1871. From 1918, Brandenburg was a province of the Free State of Prussia until it was dissolved in 1945 after World War II, and replaced with reduced territory as the State of Brandenburg in East Germany, which was later dissolved in 1952. Following the reunification of Germany in 1990, Brandenburg was re-established as a federal state of Germany, becoming one of the new states.