In the fourth and fifth decades of the twelfth century the Norman king of Sicily, Roger II, the patron of Edrisi, conquered many of the seaport towns along what is now the coast of Tunis; and, though the Latins were expelled from this region by the powerful Moroccan dynasty of the Almohads,[1408] who during the following decade came to supersede the Almoravids in the domination over North Africa and Spain, close commercial relations were maintained between the northern and southern coasts of the Mediterranean Sea throughout the century and a half with which we are concerned.[1409] The Genoese held the foremost place in the North African trade; but Pisan, Venetian, Massiliot, and Catalan merchants also frequented the markets of the seaboard towns. Under the Almohads, Ceuta and Bugia were important _entrepôts_ of Genoese trade; and when the Almohad dominions split up in the early years of the thirteenth century (1212–1238), these two towns fell into the hands of Genoa.[1410] Genoese fleets also ventured through the Strait of Gibraltar and not only tapped the commerce of the western coasts of the Iberian Peninsula but penetrated as far as Saleh on the Moroccan shore. Christians also found their way in various capacities into the interior of Maghreb, as the Moslems termed these western territories of Islam. During the Crusading epoch many Christians were taken captive in the wars in Spain and by pirates on the high seas; most of these were sold into slavery in the markets of the sea ports of Morocco, Algeria, and Tunis and sent to drag out lives of suffering in the towns of the interior. Towards the close of the twelfth century a Christian religious order was formed for the purpose of ameliorating the sufferings of the captives and of bringing about their redemption by exchange with Moslem captives held in Christendom.[1411] We have evidence that these “Redemptorists,” and the Franciscan and Dominican friars who were soon to follow them in the same work and who also served as ministers of the Christian religion to the European merchants engaged in business in Moslem countries, were not at all inhospitably received.[1412] Their work was facilitated by almost uniformly friendly relations between the papacy and the rulers of Morocco, and the number of Christians in this part of the world became so great by the fourth decade of the thirteenth century that an episcopal see was established in Fez (1233), subsequently to be removed to Morocco City.[1413] Another tie between Morocco and the Latin West was created by the maintenance at the court of the Almohads and their successors of a mercenary force composed for the most part of Spanish Christians from Catalonia and Aragon.[1414]