Subdivisions of the Polish People's Republic

After World War II, Poland lost 77,000 km² (30,000 sq mi) of eastern regions (Kresy), gaining instead the smaller but much more industrialized so-called "Regained Territories" east of the Oder–Neisse line. This annexation of German territory was agreed by the Allied Powers at the Potsdam Conference in 1945.

The Polish People's Republic was divided into several voivodeships (the Polish unit of administrative division). After World War II, the new administrative divisions were based on the pre-war ones. The areas in the East that were not annexed by the Soviet Union had their borders left almost unchanged. Newly acquired territories in the west and north were organised into the voivodeships of Szczecin, Wrocław, Olsztyn and partially joined to Gdańsk, Katowice and Poznań voivodeships. Two cities were granted voivodeship status: Warsaw and Łódź.

In 1950 new voivodeships were created: Koszalin—previously part of Szczecin, Opole—previously part of Katowice, and Zielona Góra—previously part of Poznań, Wrocław and Szczecin voivodeships. In addition, three other cities were granted voivodeship status: Wrocław, Kraków and Poznań.

In 1973, Polish voivodeships were changed again. This reorganization of administrative division of Poland was mainly a result of local government reform acts of 1973 to 1975. A three-level administrative division (voivodeship, county, commune) was replaced with a two-level administrative division (49 small voivodeships and communes). The three smallest voivodeships: Warsaw, Kraków and Łódź had a special status of municipal voivodeship; the city president (mayor) was also province governor.

The system of division remained in effect after the fall of the People's Republic, until 1999, when a system of larger voivodeships and powiats was again introduced (see Administrative divisions of Poland).

Poland's voivodeships 1945–1975 (14+2 voivodeships, then 17+5)

After World War II, the new administrative division of the country was based on the prewar one. The areas in the east that had not been annexed by the Soviet Union had their borders left almost unchanged. The newly acquired territories in the west and north were organized into the voivodeships of Szczecin, Wrocław and Olsztyn, and partly joined to Gdańsk, Katowice and Poznań voivodeships. Two cities were granted voivodeship status: Warsaw and Łódź.

In 1950, new voivodeships were created: Koszalin (previously part of Szczecin), Opole (previously part of Katowice), and Zielona Góra (previously part of Poznań, Wrocław and Szczecin voivodeships). In addition, three more cities were granted voivodeship status: Wrocław, Kraków and Poznań.