Bogusław I, Duke of Pomerania
Bogusław and his younger brother Casimir were sons of Duke Wartislaw I of Pomerania, the progenitor of the Griffin dynasty, probably from his second marriage with the Danish princess Ida.In 1164, the brothers allied with the Obotrite prince Pribislav of Mecklenburg and supported his revolt against the Saxon duke Henry the Lion.As neither Henry nor the Pomeranian dukes received any rewards from Valdemar, a lengthy conflict followed whereby Danish forces repeatedly plundered the Griffin estates.When Casimir was killed in 1180, presumably fighting against the invading troops of the Ascanian margrave Otto I of Brandenburg at Demmin, Bogusław went on to rule the Pomeranian duchy alone.One year later, Emperor Barbarossa, who had overthrown his revolting Welf rival Henry the Lion, granted Bogusław the Duchy of Slavinia (Slawia) as a fief.