From 1350 onwards the Crusade assumes a new aspect; it becomes defensive, and it is directed against the Ottoman Turks, a tribe of Turcomans who had established themselves in the sultanate of Iconium at the end of the 13th century, during the confusion and displacement of peoples which attended the Mongol invasions.
On his return to Jerusalem he was successful in repelling an attack by an army of Turcomans; and his success encouraged him to attempt the siege of Ascalon in the spring of 1153.
The expedition was to commence with a campaign against the Turcomans Herat being its later destination.
There had been operations on the banks of the Gurgan, and the Turcomans had been driven from one of their strongholds; but little or no progress had been made in the subjection.
Tile rebellion of the asafu d-daula, maternal uncle of the shah, was punished by exile, while his son, after giving trouble to his opponents, and once gaining a victory over them, took shelter with the Turcomans.