When the Gospel was first preached in Britain, the island was inhabited by Celtic peoples. In the 500's, pagan Germanic tribes, the Angles, Saxons, and Jutes, invaded Britain and drove the Christian Celts out of what is now England into Wales, Scotland, and Ireland. The new arrivals (called collectively the Anglo-Saxons) were then converted by Celtic missionaries moving in from the one side and Roman missionaries moving in from the other. (They then sent missionaries of their own, such as Boniface, to their pagan relatives on the Continent.)
In the 800's the cycle partly repeated itself, as the Christian Anglo-Saxons were invaded by the Danes, pagan raiders, who rapidly conquered the northeast portion of England. They seemed about to conquer the entire country and eliminate all resistance when they were turned back by Alfred, King of the West Saxons.
Alfred was born in 849 at Wantage, Berkshire, youngest of five sons of King Aethelwulf. He wished to become a monk, but after the deaths (all in battle, I think) of his father and his four older brothers, he was made king in 871. He proved to be skilled at military tactics, and devised a defensive formation which the Danish charge was unable to break. After a decisive victory at Edington in 878, he reached an agreement with the Danish leader Guthrum, by which the Danes would retain a portion of northeastern England and be given other concessions in return for their agreement to accept baptism and Christian instruction. From a later point of view, it seems obvious that such a promise could not involve a genuine change of heart, and was therefore meaningless (and indeed, one Dane complained that the white robe that he was given after his baptism was not nearly so fine as the two that he had received after the two previous times that he had been defeated and baptized). However, Alfred's judgement proved sound. Guthrum, from his point of view, agreed to become a vassal of Christ. His nobles and chief warriors, being his vassals, were thereby obligated to give their feudal allegiance to Christ as well. They accepted baptism and the presence among them of Christian priests and missionaries to insruct them. The door was opened for conversions on a more personal level in that and succeeding generations.
In his later years, having secured a large degree of military security for his people, Alfred devoted his energies to repairing the damage that war had done to the cultural life of his people. He translated Boethius' Consolations of Philosophy into Old English, and brought in scholars from Wales and the Continent with whose help various writings of Bede, Augustine of Canterbury, and Gregory the Great were likewise translated. He was much impressed by the provisions in the Law of Moses for the protection of the rights of ordinary citizens, and gave order that similar provisions should be made part of English law. He promoted the education of the parish clergy. In one of his treatises, he wrote:
"He seems to me a very foolish man, and very wretched, who will not increase his understanding while he is in the world, and ever wish and long to reach that endless life where all shall be made clear."
He died on 26 October 899, and was buried in the Old Minster at Winchester. Alone among English monarchs, he is known as "the Great."
The writer G K Chesterton has written a long narrative poem about Alfred, called, "The Ballad of the White Horse." In my view, it would be improved by abridgement (I would, for example, terminate the prologue after the line "And laid peace on the sea"), but I think it well worth reading as it stands, both for the history and (with minor reservations) for the theology.
O Sovereign Lord, who didst bring thy servant Alfred to a Troubled throne that he might establish peace in a ravaged land and revive learning and the arts among the people: Awake in us also, we beseech thee, a keen desire to increase our understanding while we are in this world, and an eager longing to reach that endless life where all will be made clear; through Jesus Christ our Lord, who liveth and reigneth with thee and the Holy Spirit, one God, for ever and ever.
O Sovereign Lord, who brought your servant Alfred to a troubled Throne that he might establish peace in a ravaged land and revive learning and the arts among the people: Awake in us also a keen desire to increase our understanding while we are in this world, and an eager longing to reach that endless life where all will be made clear; through Jesus Christ our Lord, who lives and reigns with you and the Holy Spirit, one God, for ever and ever.