en.wikipedia.org/wiki/Name_of_Poland Language roots It is sometimes assumed that all of the above names derive from the name of the Polans (Polanie), a West Slavic tribe which inhabited the territories of present-day Poland in the 9th-10th centuries. The origin of the name Polanie itself is uncertain and the earliest references to it appear among East Slavs in the area around the Dnieper River. It may derive from the word pole, Polish for "field".
Many ancient tribes in Europe derived their names from the nature of the land they inhabited. Gervase of Tilbury wrote in his Otia imperialia ("Recreation for an Emperor", 1211): Inter Alpes Huniae et Oceanum est Polonia, sic dicta in eorum idiomate quasi Campania.(translation: "Between the Hunnic Alps and the Ocean there is Poland, thus called "Countryside" in their idiom.") Polans may have used Polska to describe their own territory in the Warta River basin. During the 10th century, they managed to subdue and unite the Slavic tribes between the rivers Oder and Bug River into a single feudal state and in the
early 11th century, the name Polska was extended to the entire ethnically Polish territory. The lands originally inhabited by the Polans became known as Staropolska, or "Old Poland", and later as Wielkopolska, or "Greater Poland", while the lands conquered towards the end of the 10th century, home of the Vistulans (Wiślanie) and the Lendians, became known as Małopolska, or "Lesser Poland."