BRANDENBURG ~ Province and Land.
In 1813-15 the Kingdom of Prussia recovered lost lands and gained new ones, and in consequence its provinces were reorganised. The Mittelmark, the Neumark, Priegnitz, and Uckermark from the old Electorate were joined together with Upper and Lower Lusatia (Lausitz) to form the province of Brandenburg; the Altmark, the western part of the former Electorate, which was restored to Prussia, became part of Sachsen (Prussian Saxony).
In 1920 Berlin, which had long before displaced the town of Brandenburg as capital, officially became a separate province, though it had been generally regarded as one for several years before that.
After the Second World War, the bulk of the old Neumark, lying east of the Oder-Neisse line, became part of Poland. The remainder of Brandenburg became a Land in the Soviet Zone and later in the German Democratic Republic until 1952, when it was broken up. The administrative districts of Potsdam, Frankfurt, and Cottbus were formed entirely or largely from Brandenburg territory, whilst parts of the Land joined the Schwerin and Neubrandenburg districts to the north.
Just before German reunification in 1990 the Land of Brandenburg was reconstituted. Potsdam is its capital and it is divided into 6 Stadtkreise and 44 Landkreise. It is 5th in area of the Länder, but only 11th in population.