The Seljuk Turks came from central Asia. They captured much of the Middle East, which they won from the Arabs. They became Muslims, and became fanatical. In the Roman church, it was encouraged that Christians journey to Israel, the Holy Land. The Seljuk Turks were violent to these pilgrims, and, 1071 A.D., won the Battle of Manzikert, taking a large portion from Christendom. The church found out, and Pope Urban II “… responded enthusiastically by proclaiming the beginning of crusades for the western European, Roman control of the Holy Land.” History Book, page 153. I think the Seljuk Turks affected our world in the Middle Ages, because they affected the decision of the pope to begin the crusades.