To Arab historians, the Crusaders were a minor irritant, their invasion of one more barbarian incursion, not nearly as serious a threat as the Mongols were to prove in the thirteenth and fourteenth centuries.The First Crusade began in 1095 after the Byzantines – threatened by Seljuk power- appealed to Pope Urban II for military aid. Pope Urban, hoping to divert the Christian kings and princes from their struggles with each other, and...