Isaac Komnenos (son of Alexios I)

Isaac Komnenos (1093–after 1152), third son of Emperor Alexios I, was a porphyrogennetos. He helped his brother John II take the throne in 1118 and became sebastokrator, but conspired against John from 1130 and spent years exiled in Asia Minor and the Levant.

Pardoned in 1138, he was exiled again in 1139 after his son defected to the Seljuk Turks, and in 1143 backed the losing claimant against Manuel I. Forced into retirement in 1150, he founded the Kosmosoteira Monastery and wrote its charter in 1152, and rebuilt the Chora Church. His son Andronikos I later seized the throne.