In this paper, the process of advent of Crusaders and Mongols into the Middle East, who carried out invasive campaigns to this geography in the period between XI. and XIII. Centuries, and motives that led them to these invasions will be examined. These two military campaigns were carried out aiming at Medieval Islamic civilization led by Turks and left deep traces in the history of Middle East. Mongolian invasion, which took place in the period when Crusaders’ rule in Anatolia, Iraq and Syria began to fade and was confined to small castles, was met with excitement by Christians in the region and the alliance that was desired between the two parties against Muslims, the local elements sparked off political, religious and trade interactions. ...