The Polans (also known as Polanes, Polanians; Polish: Polanie, derived from Old Slavic pole, "field" or "plain", see polje) were a West Slavic tribe, part of the Lechitic group, inhabiting the Warta River basin of the historic Greater Poland region in the 8th century.
In the 9th century the Polans united several West Slavic groups to the north of Great Moravia. The union led by the Piast dynasty developed into the Kingdom of Poland, whose name derives from that of the Polans.
The earliest Polan rulers mentioned by name are the legendary figures of Piast the Wheelwright and Popiel (8th–9th centuries). The first historical ruler was Mieszko I (960–92), who enlarged the Polish territory by incorporating Masovia and conquering Silesia and the Vistulan lands of Lesser Poland.
The Dagome iudex document refers to Poland during Mieszko's reign as Civitas Schinesghe (The Gniezno State). The document describes the country as stretching between the Oder and Rus and between Lesser Poland ("Craccoa"/"Alemure") and the Baltic Sea. For more information, see Poland in the Early Middle Ages and History of Poland during the Piast dynasty.