The Crusades began with a help the pilgrims to save them from the Muslim dominance and attacks. But, it had some bad results, such as weakening the feudal system, millions of causalities on both sides, and causing a broad range of slavery, although it had some good results. Through the Crusades, the Crusaders interacted with other people in the lands they travelled and fought. The Medieval Europe was in the Dark Ages, although the Eastern people had some modern technology and life that it was better than the one in Europe. The Europeans learned mathematics, engineering and warfare from the Eastern people, and they brought these ideas home that it was a gain. Merchants and traders brought spices, fruit and other commodities from the East. The
