The feudal system adopted by the Seljuks caused endless dissension
among their petty sovereigns, called "Atabegs", all of whom were
nominally vassals of the Caliph at Bagdad. Thus it came about that
Islamism, divided against itself, offered but a poor resistance to the
advance of the Christians. The Crusaders had little difficulty in
making their way to Palestine. They captured Jerusalem, and
established the Latin kingdom there.

By the middle of the twelfth century Mohammedan power had shrunk to
smaller dimensions. Not only did the Franks hold Palestine and all the
important posts on the Syrian coast, but, by the capture of Lesser
Armenia, Antioch, and Edessa, they had driven a wedge into Syria, and
extended their conquests even beyond the Euphrates.

At length there came a pause in the decline of Islam. Zengi, a
powerful Seljuk Atabeg, in 1144 captured Edessa, the outpost of
Christendom, and the Second Crusade, led by the Emperor Conrad of
Germany and by King Louis VII of France, failed to effect the
recapture of the fortress. Nureddin, the far-sighted son and successor
of Zengi, and later on Saladin, a Kurd, trained at his court,
discovered how to restore the fallen might of Islam and expel the
Franks from Asia. A necessary preliminary step was to put an end to
the dissensions of the Atabeg rulers. Nureddin did this effectually by
himself annexing their dominions. His next step was to gain possession
of Egypt, and thereby isolate the Latin Kingdom. Genoa, Pisa, and
Venice, the three Italian republics who between them had command of
the sea, were too selfish and too intent upon their commercial
interests to interfere with the designs of the Saracens. The Latin
king Amalric had for some years sought to gain a foothold in Egypt. In
November, 1168, he led the Christian army as far as the Nile, and was