Having achieved their goal in an unexpectedly short period of time, many of the Crusaders departed for home.
Those who remained governed the conquered territory and established 4 large Crusader states in Jerusalem, Edessa, Antioch and Tripoli. Guarded by formidable castles, the Crusader states retained the upper hand in the region until around 1130.
In 1144, the Seljuk general Zangi, governor of Mosul, captured Edessa, leading to the loss of the northernmost Crusader state.
News of Edessa’s fall stunned Europe, and led Christian authorities in the West to call for another Crusade. Led by two great rulers, King Louis VII of France and King Conrad III of Germany, the Second Crusade began in 1147.
The Turks crushed Conrad’s forces at Dorylaeum. After Louis and Conrad managed to assemble their armies at Jerusalem, they decided to attack the Syrian stronghold of Damascus with an army of 50,000 (the largest Crusader force yet).
The combined Muslim forces dealt a humiliating defeat to the Crusaders, decisively ending the Second Crusade; Nur al-Din would add Damascus to his expanding empire in 1154.