Gathering the shards of a little-known folklore
The characters and concepts in the Blood of Woden books are drawn from the faith and beliefs of the heathen English. These beliefs were widespread until the end of the seventh century, but from then on they were gradually replaced by the teachings of the Church. Open worship of the old gods probably ended in the eighth century, but belief in elves and giants lasted far longer, as did the memory of the old ways. A belief in the Wyrd - the hand that twisted fate - has never truly ended.
The names and ideas in this modern-day adventure are presented as faithfully as they can be from the surviving information. The problem is that so little has survived. Most of what is known of the old faith has been pieced together from place names, archaeology and the odd scrap of written evidence from poems such as Beowulf. This dearth of information is down to three things: firstly, the pre-Christian English seldom wrote anything down; secondly, they carved mostly in wood, so little of their work has survived; thirdly, the church rewrote or rebranded much of the lore that remained.
We do know that the English believed in a number of worlds, a range of supernatural beings, a pantheon of gods and an all-powerful, all-controlling fate. That said, the evidence is scant, often no more than a single passing mention.
Thankfully, the English shared their faith with their fellow Germanic nations, including those in Iceland and Norway. In these northern lands, at the very end of the heathen era, two books were written which, between them, contain almost all the tales we have of the old gods. These books are known as the Eddas. The Poetic Edda is a collection of tales and poems brought together in the eleventh century (although some say as late as the thirteenth). The Prose Edda is a single work by a man named Snorri Sturluson, written in Iceland around 1220.
What is interesting is that the few English sources which do show or mention the gods match these Icelandic tales almost exactly. For example, Beowulf was composed in England around the year 800. It contains the following fleeting reference to someone named Hama.
This is the only mention of Hama in the whole of Beowulf. It is included in the poem purely to make the point that the treasure the writer is describing is almost as good as the jewel called Brosingamen, which Hama brought to the "bright borough" i.e. the home of the gods. That Hama is mentioned only as an aside implies the listeners knew who he was and, furthermore, that they had heard the tale of Hama and Brosingamen many times before.
In the Prose Edda, Sturluson tells us that the Norse god Heimdallr swam out to an island to fight Loki, who had stolen Freyja's necklace, Brisingamen, and hidden it on the island. Heimdallr won and returned to Asgarthr (the "bright borough") with the gem, which he then gave back to Freyja.
This is almost certainly the same tale. Hama and heim are the words for 'home' in Old English and Old Norse respectively. From this one reference in Beowulf, we know that the English both knew Hama as a god and knew at least some of the legends surrounding him.
Likewise, the Norse poem Volundarkvith tells the tale of how master smith, Volundr, was imprisoned by an evil king. In revenge, he killed his captor's sons and made drinking cups out of their skulls, which he then presented to the king as a gift. When the boys' sister came to call, he hid their bodies under his bellows.
This very scene appears on the side of the Franks Casket, an eighth century whalebone box carved with runes and with scenes from Germanic folklore. Just as in the poem, Volundr (known as 'Weland' or 'Wayland' in English) is shown holding a boy's head in his tongs while hiding the rest of his body under the bellows. What is interesting is that this box was made in England some three hundred years before Volundarkvith was written down.
If these tales could survive unaltered for so long then who is to say that others could not do the same? What is frightening is that, were it not for these happy survivals, we would have not a shred of evidence that the English knew any of the later Norse tales.
As it is, a glimpse may have to be enough.