During the Early Middle Ages, Muslim polities of the Middle East and North Africa and Christian kingdoms of Europe often banned each other's merchants from entering their ports. Privateers of both sides raided the shipping of their adversaries at will. The Radhanites functioned as neutral go-betweens, keeping open the lines of communication and trade between the lands of the old Roman Empire and the Far East. As a result of the revenue they brought, Jewish merchants enjoyed significant privileges under the early Carolingian dynasty in France and throughout the Muslim world, a fact that sometimes vexed local Church authorities.