Poznań Voivodeship was the name of several former administrative regions (województwo, rendered as voivodeship and usually translated as "province") in Poland, centered on the city of Poznań, although the exact boundaries changed over the years. Poznań Voivodeship was incorporated into the Greater Poland Voivodeship after the Polish local government reforms of 1998.
Poznań Voivodeship (Latin: Palatinatus Posnaniensis) was established in 1320 and was part of the Greater Poland Voivodeship, until it was annexed by Prussia in 1793.
Between 1793 and 1921, the territory formerly contained in Poznań Voivodeship was part of the following territories: South Prussia, the Poznań Department of the Duchy of Warsaw, the Grand Duchy of Posen, and the Province of Posen in Prussia.
After World War I, Poznań Voivodeship was created from the Prussian-German province of Poznań. The borders were changed in 1939: Bydgoszcz passed to the Pomeranian Voivodeship, but some Eastern areas were included. After the changes, the area was 28,089 km² with a population of 2,339,600 people (see: Territorial changes of Polish Voivodeships on April 1, 1938).
During World War II, Poland was occupied by Nazi and Soviet forces and the territory annexed by Germany was named the Reichsgau Wartheland, which partially overlapped with the former Province of Posen and also had Poznań/Posen as its capital.