Greater Poland, often known by its Polish name Wielkopolska is a historical region of west-central Poland. Its chief and largest city is Poznań followed by Kalisz, the oldest city in Poland.

Greater Poland, sometimes called the “cradle of Poland,” formed the heart of the 10th-century early Polish state. Poznań and Gniezno were early centers of royal power, but following the region’s devastation by pagan rebellion in the 1030s, and an invasion by Bretislaus I of Bohemia in 1038, the capital was moved by Casimir the Restorer from Gniezno to Kraków.

The boundaries of Greater Poland have varied somewhat throughout history. Since the Middle Ages, the proper Wielkopolska land was split into the Poznań and Kalisz voivodeships. In the wider sense, it encompassed also Sieradz, Łęczyca, Brześć Kujawski and Inowrocław voivodeships which were situated more eastward. After the Partitions of Poland at the end of the 18th century, Greater Poland was incorporated into Prussia as the Grand Duchy of Posen. The region in the proper sense roughly coincides with the present-day Greater Poland Voivodeship (Polish: województwo wielkopolskie).

Similarly to the historical regions of Pomerania, Silesia, Mazovia or Lesser Poland, the Greater Poland region possesses its own distinctive folk costumes, architecture, cuisine, dialect and other traditions that differ from other parts of Poland.