ISAAC II ANGELUS, EMPEROR OF THE EAST. — He was emperor twice: from 1185 to 1195 and, with the aid of the Latins, from August 1203 to January 1204. His reign was very turbulent. He obtained the throne by a violent act in 1185 and lost it through a revolutionary plot by his brother Alexius III (1195–1203), who had him blinded.
Among the acts of his reign stand out the imperial diplomas granted to the Italian republics of Venice, Genoa, and Pisa, his treaty with the Sultan of Egypt Ṣalāḥ al-Dīn against the Latin expedition of the Crusade of Emperor Frederick I, and certain ordinances concerning monastic law (Patmos, Athens), matrimonial law (dispensation from the impediment of the seventh degree of consanguinity in one case), the new arrangement regarding the organization of episcopal sees (taxis), and finally the prohibition imposed on bishops against contracting marriage and even cohabiting with a spouse.
It has therefore been rightly said that I. followed the system of caesaropapism; even toward the Roman Church he showed little sympathy during his first reign, but in his second he acknowledged the primacy of the pope.