During these later centuries of the Saxon period, from 800 to 1066, the most conspicuous and most influential ruler was King Alfred. When he became king, in 871, the Danish invaders were so completely triumphant as to force him to flee with a few followers to the forest as a temporary refuge. He soon emerged, however, with the nucleus of an army and, during his reign, which continued till 901, defeated the Danes repeatedly, obtained their acceptance of Christianity, forced upon them a treaty which restricted their rule to the northeastern shires, and transmitted to his son a military and naval organization which enabled him to win back much even of this part of England. He introduced greater order, prosperity, and piety into the church, and partly by his own writing, partly by his patronage of learned men, reawakened an interest in Anglo-Saxon literature and in learning which the ravages of the Danes and the demoralization of the country had gone far to destroy. Alfred, besides his actual work as king, impressed the recognition of his fine nature and strong character deeply on the men of his time and the memory of all subsequent times. The power of the kingship in the Anglo-Saxon system of government was strengthened by the life and work of such kings as Alfred and some of his successors. There were other causes also which were tending to make the central government more of a reality. A national taxation, the Danegeld, was introduced for the purpose of ransoming the country from the Danes; the grant of lands by the king brought many persons through the country into closer relations with him; the royal judicial powers tended to increase with the development of law and civilization; the work of government was carried on by better-trained officials. On the other hand, a custom grew up in the tenth and early eleventh century of placing whole groups of shires under the government of great earls or viceroys, whose subjection to the central government of the king was but scant. Church bodies and others who had received large grants of land from the king were also coming to exercise over their tenants judicial, fiscal, and probably even military powers, which would seem more properly to belong to government officials. The result was that although the central government as compared with the local government of shires and hundreds was growing more active, the king's power as compared with the personal power of the great nobles was becoming less strong. Violence was common, and there were but few signs of advancing prosperity or civilization, when an entirely new set of influences came into existence with the conquest by the duke of Normandy in the year 1066.