Sources https://en.wikipedia.org/wiki/Lestek
Medieval Lands:
LESZEK (-[921]). The Annales Polanorum state that "Semovith genuit Lisekonem". The Chronicæ Polanorum names "Lestik filius Semovith", specifying that he succeeded his father. He succeeded his father in [892] as ruler of the Polanians, until 913. m ---. The name of Leszek's wife is not known. Leszek & his wife had one child: SIEMOMYSŁ