His father , who defeated the Siculo - Norman invasion of Byzantium at the Battle of Demetritzes , was killed in 1187 when leading a rebellion against Isaac II Angelos .
He was a descendant of the imperial dynasty of the Komnenoi through both his parents .
descendant 's father , who defeated the Siculo - Norman invasion of Byzantium at the Battle of Demetritzes , was killed in 1187 when leading a rebellion against Isaac II Angelos .
He was a descendant of the imperial dynasty of the Komnenoi through both his parents .