While those who participated in the Second Crusade had probably planned to do so before hearing of the loss of Edessa to Zangi, the urgency of the crusade was likely reinforced by the loss. Pope Eugenius III issued a crusading bull (Quantum praedecessors) to Louis VII of France. A Cistercian abbot, Bernard of Clairvaux, convinced Conrad III of Germany to go on crusade as well. Louis VII and Conrad III arrived in Constantinople in 1147. The crusaders then attacked Damascus, a Muslim city that had been allied to the Christians until the attack. Upon the arrival of Nur al-Din (Nureddin) and his forces, the crusaders gave up their siege, ending the Second Crusade. It is important to note that the majority of the crusaders during this period crusaded either in Iberia (where they seized Lisbon) or (more unsuccessfully) on the eastern border of Germany against the Slavs and Wends.
While the Second Crusade didn't directly help the Christian presence in the Mideast, from 1153 to 1169 the Franks were again on the offensive. However, the attack on Damascus probably also helped Nur al-Din gain control of Damascus in 1154. Nur al-Din was the son of Zangi and inherited Aleppo (but not Mosul) from his father. Nur al-Din continued to increase his power; by 1155, he had united Muslim Syria. From 1163-69, Shirkuh, one of his generals, struggled for control of Egypt. Two months after Shirkuh gained control of Egypt for Nur al-Din, leaving Shirkuh's nephew Saladin in charge of Egypt. In 1170, Nur al-Din finally gained Mosul.
At the time of his death on May 15, 1174, Nur al-Din controlled Syria and Egypt. A power struggle for control of his son ensued upon his death, ending for the moment Muslim unity. Saladin, who already had control of Egypt, now fought for control of Syria: he took Damascus in October 1174, Aleppo in June 1183, and Mosul in Febuary 1186. While Saladin did occasionally attack the Christian forces, he focused more of his attention on consolidating power in Syria and Jazira. By 1187, however, he had control of Syria and Egypt and his attention turned toward the Latin settlements. In attacking a Muslim caravan (which was protected by virtue of a peace treaty), Reynald of Transjordan provided Saladin with a reason to end this treaty and start his attack.
The Christians had been on the defensive since 1169. Baldwin V of Jerusalem died in August 1186, and his mother and aunt fought for control of Jerusalem, leaving the Christians with a crisis of leadership. Saladin invaded the Frankish territory in 1187 and in July of that year defeated the combined armies of the crusader states at the Battle of Hattin. The destruction of the army left the territories vulnerable and Saladin was able to retake Jerusalem and most of the territory of the Crusaders, leaving only Tyre, Tripoli and Antioch. These were, however, enough of a foothold for reinforcement and the Third Crusade to enter the Mideast.
To see a summary of the First Crusade and subsequent events, click here.
To see a summary of the Third Crusade and subsequent events, click here.
To see a more detailed list of events during this period, click here.