Subdivisions of the Polish–Lithuanian Commonwealth evolved over for centuries of its existence from the signing of the Union of Lublin to the third partition.
The lands that once belonged to the Commonwealth are now largely distributed among several central, eastern, and northern European countries: Poland (except western Poland), Lithuania, Latvia, Belarus, most of Ukraine, parts of Russia, southern half of Estonia, and smaller pieces in Slovakia and Moldova.
Greater Poland, often known by its Polish name Wielkopolska (Polish: [vjɛlkɔˈpɔlska] ; Latin: Polonia Maior), is a Polish historical region of west-central Poland. Its chief and largest city is Poznań followed by Kalisz, the oldest city in Poland.
The boundaries of Greater Poland have varied somewhat throughout history. Since the Late Middle Ages, Wielkopolska proper has been split into the Poznań and Kalisz voivodeships. In the wider sense, it also encompassed Sieradz, Łęczyca, Brześć Kujawski and Inowrocław voivodeships (the last two known as Kuyavian) which were situated further east, and the Santok Land, located to the northwest. The region in the proper sense roughly coincides with the present-day Greater Poland Voivodeship (Polish: województwo wielkopolskie).
View the full Wikipedia page for Greater Poland