Page:The Fall of Constantinople.djvu/134

 116 THE FALL OF CONSTANTINOPLE. which was not repeatedly attacked, and these attacks were often, as in the case of Tancred's expedition, and as in the case of the Turkish attack following the accession of Androni- cos, due directly to the dynastic troubles ; while in other cases, where it is inexact to say that they were the direct cause, the attacks were invited by the disturbed state of the empire. The opposition of pretenders to the throne, the struggles and differences in the imperial family within the city, and the at- tacks from without, contributed tremendously to the weaken- ing of the empire.