Nicetas Choniates, Historia.

Translated by George B. Stow, Jr.  Reprinted in The Latin Conquest of Constantinople.  Edited by Donald E. Queller.  London:  John Wiley, 1971. pp. 82-83.

        "Emperor Alexius III removed his brother Isaac from office.  Negligent of the need for a guard over Isaac, Alexius forgot that great misfortunes sear themselves indelibly into the minds of men, and that one cannot always lull justice to sleep, but that later revenge, although dormant for a long time, loves to crash down unexpectedly upon those committing unjust deeds.  Alexius allowed his brother to lead a free life in the quarter of the city near the two columns which stand on the shore next to the crossing, where anyone might visit him without fear of reproach.  Many people, especially the Latins, sailed over to Isaac, conferred with him regarding common interests, and presented secret plots to avenge themselves and to overthrow Alexius.  Accordingly, Isaac sent letters to his daughter Irene, the wife of Philip of Swabia, ruler of the Germans, and implored her to avenge her father.  He then received letters in reply, in which Irene asked what was to be done.

    Later, the emperor released even Alexius, Isaac's son, from custody, and allowed him to move about freely.  As the emperor was occupied with preparations to move against the Protostrator [Manuel Kamytzes, a campaign that took place in 1201, thus placing the escape of Alexius and his presence in the West a year earlier that Villehardouin suggests], young Alexius was taken along to Damokraneia, where the royal party halted.  There Alexius, doubtless on the advice of his father, came to an agreement with a Pisan, who commanded a great merchant ship, and waited for a favorable opportunity to escape to sea.  When the moment was propitious for departure, the ship set sail, and, urged by a favorable wind, came to Aulonia on the Hellespont. Its small boat then continued on to pick up Alexius.  In order that no one might discern the true plan, however, it took on sand to serve as ballast for the great cargoless ship. Alexius approached in haste from  Damokraneia, boarded the skiff, and was rowed across to the great ship.

    When his escape was discovered, the emperor dispatched agents, who were ordered to track down the ship.  They, however, could not find Alexius, because he had cut off his hair all around, and had put on clothes such as the Latins wear.  Thus disguised in the great band of Latins, Alexius was able to elude his pursuers and to proceed to Sicily, and his arrival was made known to his sister.  Having dispatched a sufficient guard for his protection, when Alexius arrived his sister embraced him, and she sought the power of her husband Philip to assist her father, unjustly deprived of his sight and rule.  Irene also implored her husband to assist her homeless and countryless brother, wandering about empty-handed, life a planet in the heavens."