 Jan Dlugosz may have easily misinterpreted the nickname, being chronologically remote to the political context of Łokietek's era.In 1267, when Władysław I Łokietek was seven years old, his father Casimir died.At this time, Leszek II the Black inherited Łęczyca (he had already been given Sieradz six years earlier), Ziemomysł gained Inowrocław, and Brześć Kujawski and Dobrzyń were held in regency by Eufrozyna on behalf of Władysław and his younger brothers Casimir II and Siemowit.