Prior to the coming of the Romans beginning (not really) in 55BC, there were Britons, a Celtic people. They shared deep ancestry with the Germanic and Italic peoples and even cultural similarities, but were long-sundered cousins, and none of the groups would have recognised it. They had replaced the people who built Stonehenge thousands of years before. We are only now learning much about any of these people, because of archaeology. Records, not so much.
When the Romans really started coming in, they did not bring any Christianity at the beginning, but their elites increasingly included such believers, and by the 300s it had become the official religion of the Empire, and the elites especially embraced it. The conquered, peasant, heathen, string-of-negative-adjective Britons embraced Christianity very irregularly, and as the Romans left beginning in the late 300s, the older, traditional Celtic beliefs slowly became the norm again. We call this the Dark Ages, not because we don't like the Britons and think they are stupid ( though we did and that did influence later historians) but because they were illiterate and we have almost nothing from written sources about them, and even less from them. A few inscriptions is it for the latter.
Entertaining digression, because that's why you come here, admit it: one can still find lots of people referring to the Ages being called Dark because it was the age of faith, when everyone was under the oppressive control of Christian priests. It's one of those ideas that just won't die, because so many people want it to be true. Facts are troublesome things. The Dark Ages are in fact bookended by Christianity, which if nothing else, wrote things down. The Ages were Dark because we don't have any written records and have to stumble about in the Dark guessing where the deities, gold jewelry, and sugar cookies were being kept in this Age. Rather than apologise for this lack of solid info at every turn, I have decided to embrace it for this discussion. It is not just a joke, though I will treat it that way. It is highly revelatory what current scholars, previous scholars, 21st C popular culture and 18th-20thC popular cultures do when confronted by limited hard evidence. If you are into historiography, you might find that contemplation more interesting than any spurious list of Anglo-Saxon goddesses who were really Spunky Gals on the neopagan sites.
Back to the cliffhanger, where we left the Romano-Briton elites being slowly abandoned by the Romans around 400. Archaeology keeps bending our dates so that we find the Romans started jumping ship ever-earlier, and the various Germanic invaders showed up ever-earlier. Not really a problem. We make categories in order to break them. The Angles, Saxons, Frisians, and Franks started looting and extracting tribute in the 400s, and even the occasional Jute may have shown up for the spoils. They were illiterate, and we don't have records.
Scholars take a long time to say we don't know anything for sure but gee, this sure looks like it could be...
I suppose none of us can quite avoid that.
The A-S peoples settled in like the owned the place over the next few centuries, until the Danes and other Vikings came in in the 700s and enacted the same scenario of looting, extracting tribute, then protection money, and eventually scooping up the best land and wives. The Saxons formed from villages and farmsteads to first The Heptarchy,
petty kingdoms from about 500, eventually coalescing into the more
familiar Mercia, Wessex, Northumbria, and East Anglia in the 700s. In the meantime, a few of their monks had picked up writing and history, and just as they were all starting to be overrun, began to record history, including what the pagans were doing out in the provinces.
Monks? Oh yes, in the meantime after the Roman-Briton elites and their Christianity disappeared, there were external efforts made to convert the Angles, etc, and these had some success. Augustine (not that Augustine) came in and became archbishop of Canterbury. Also, Augustine had the tremendous advantage of landing at Thanet which 1066 and All That assures us is the key to conquering Britain. (Haha. Joke.) A lot of the Christianity wouldn't be recognised by too many denominations today, but they at least had the children baptised, got married in church, and went to Mass. This Christianity had penetrated enough that the Anglo-Saxons thought of themselves as Christians, whatever leftover pagan practices they had, and considered the invading Vikings The Great Heathen Army. But even those became Christian in the next few centuries. We won't get into that, except to note that when we find something pagan still hanging around in Britain today, we should remember that it could have originated in any of these historical layers.
The Danes were distant cousins, though no one treated each other that way, but they notably had at least some writing as well, just not right there in Britain at first. The Dark Ages gave way to the Okay, Darkish Ages.


