THE NORTHMEN AND OTHER INVADERS 227 beyond the Tiber to protect the basilica of St. Peter and the Vatican Palace. From 847 to his death in 875 the Emperor Louis II, son of Lothair, led frequent expeditions against the Saracens without succeeding in driving them out of Italy entirely, chiefly for the reason that the petty lords who now divided the old Duchy of Benevento between them did not co- operate loyally with him. In 871, acting in unison with a Byzantine fleet, he captured Bari from the Moslems; and the Byzantine Emperor Basil, who continued the struggle after Louis's death, at last expelled them from the east coast and southern end of the peninsula. But they still held posts farther up the west coast from which they often plundered central Italy, until Pope John X finally got rid of them in 915. In Sicily their rule endured into the eleventh century and Palermo became a center of prosperity, refinement, and learning comparable to Bagdad, Cairo, and Cordova. But the state was weakened by the jealousies between the Arabs and Berbers. Toward the close of the ninth century the nomadic Magyars entered the plain of Hungary, whence the Avars had disappeared soon after Charlemagne. The incursions by I Magyars to-day form the ruling class in Hungary, the Magyars Again and again during the first half of the tenth Hungary i century they swept over Bavaria, Saxony, Thuringia, and j Franconia ; they frequently ravaged Lombardy beyond the iAlps; and their devastations in Gaul sometimes carried them as far as Spain or Flanders. It was the business of the kings of the East Franks to stop these invaders, but for many years they failed to do so. Arnulf (887-899) imade an alliance with them. Louis the Child (899-911) was defeated by them and forced to pay them tribute. They invaded four times during the brief reign of Conrad I, who had many other wars on his hands. Henry I (919- 936), whose authority was restricted to Saxony and Thu- ringia, gained immunity for those districts for a number of years by paying tribute, and the Magyars turned their at- i tent ion to Bavaria, whose duke was practically independent
