With the capture of Ascalon the southern border of the kingdom was now secure, and Egypt, formerly a major threat to the kingdom but now destabilized under the reign of several underaged caliphs, was reduced to a tributary state. Nur ad-Din remained a threat in the east, and Baldwin had to contend with the advances of Byzantine emperor Manuel I Comnenus, who claimed suzerainty over the Principality of Antioch. In order to bolster the defences of the kingdom against the growing strength of the Muslims, Baldwin III made the first direct alliance with the Byzantine Empire, by marrying Theodora Comnena, a niece of emperor Manuel; Manuel married Baldwin's cousin Maria. As William of Tyre put it, it was hoped that Manuel would be able "to relieve from his own abundance the distress under which our realm was suffering and to change our poverty into superabundance".