226 THE HISTORY OF MEDIEVAL EUROPE civilization of the regions with which they came in contact. Third, a capacity for ruling, organization, and government which shows itself in their founding of the principality of Russia, of the Duchy of Normandy, of the republic of Ice- land, and later in the Danish and Anglo-Norman monarch- ies in England, and in the Norman kingdom of Sicily and southern Italy. While the Northmen were sailing up the rivers which empty into the North Sea, the English Channel, and the Bay The Sara- of Biscay, Mohammedan pirates raided from the and S ^uth°- lly Mediterranean, and the shores of southern Italy em Italy are still lined with the ruins of towers built to guard against them. In 827, when they were called in by Christian rebels, a native Berber dynasty in North Africa began to wrench Sicily away from the Byzantine Empire. Palermo, on the northern coast, was taken in 831 and be- came the Moslem capital; most of the island was subjugated by the middle of the same century ; then came a lull before Syracuse, on the eastern coast, was destroyed in 878, and the conquest was not complete until 902. Long before that, however, the Saracens had entered Italy. The Duke of Naples called upon them in 837 to relieve that town from a siege by the Lombard Duke of Benevento. A few years later the Neapolitans returned the favor by helping the Saracens to conquer Messina in the extreme northeastern corner of Sicily. Meanwhile the Moslems were making con- quests in Italy, especially since Benevento had split into two halves which kept fighting each other. Moslems from Crete took one side in this strife and Moslems from Sicily took the other side. They also pushed far up the Adriatic Sea and defeated the Venetians. They made Bari in Apulia their headquarters, and from that point overran southern Italy pretty much as they pleased. In 846 their fleet entered the seaport of Rome and plundered the suburbs and broke open the graves of St. Peter and St. Paul in their churches outside the walls. Three years later a similar expedition was defeated by a fleet from Italian towns of the west coast, as- sisted by a storm; and a wall was built around the quarter
