The conversion of the Northmen has an interesting history.[251:1] The political situation in the tenth century opened the way for the introduction of Christianity. Hakon the Good, educated in England as a Christian, conquered and united all Norway, converted his followers, called over priests from England, and sought to force Christianity upon all his people, but in this failed. The sons of Eric, also Christianised in England, wrested the throne from Hakon the Good in 961, and likewise tried to uproot paganism, but they, too, were unsuccessful. Olaf, of romantic career, was called in 995 to rule. He, likewise, waged a crusade in behalf of Christianity and with such success that when he died in 1000, it had been permanently established. Olaf the Saint (1014-1030), however, completed the Christianisation of Norway and put it under the protection of the Archbishop of Bremen-Hamburg.[252:1] As early as the eighth century, Culdee anchorites were accustomed to retire to Iceland from Scotland. In the ninth century Norwegians began to flee thither from the tyranny of their kings. Most of these emigrants were pagans, but one Norwegian convert in Saxony persuaded Bishop Frederick to go with him to Iceland where the bishop remained four years, but made little impression. Thougbrand journeyed thither in the tenth century, but likewise largely failed in his efforts. After the conversion of Norway, however, the intimate relations with Iceland soon produced different results. Christianity spread so rapidly that in 1000 the Christian religion was made the state religion. The first church built on the island was from timber sent by Olaf the Saint.[252:2] Greenland was discovered and colonised by the bold Icelander, Eric the Red, in 986, and Eric's son was sent over by Olaf to plant the Christian Church there in 1000. The Church flourished there for four hundred years until disrupted by the Esquimos. About the year 1000 Vinland was discovered and thus the Gospel was known on the coast of New England five centuries before Columbus appeared.[253:1] Like the Danes, the Swedes learned of Christianity through wars and conquests, and commercial relations. Björn, the Swedish King, asked Louis the Pious to send him Christian missionaries. Accordingly in 829 Ansgar, expelled from Denmark, went to Sweden where he laboured two years with some success. Five years later he sent Gautbert and Nithard to Sweden with a number of priests, but the pagan uprising killed all the priests and soon swept away all traces of Christianity. In 848 Ansgar made a pompous visit to Sweden again with costly presents and letters, and reopened the field for missionary work. By the eleventh century, the King of Sweden and his sons were baptised, and the work was pushed with renewed vigour, although it was not until the middle of the twelfth century that the conversion of Sweden was completed.