The known facts of history can only get you so far toward understanding it. If you are interested in, say, the Vikings in Britain, what evidence can you find? You have contemporary writtern sources like saints' lives and the Anglo-Saxon Chronicle, and a small body of Old English poetry. You have a larger body of Norse verse and prose that purports to describe this period, but most of it was written down centuries later. You have artifacts like swords, cooking pots, and jeweled reliquaries. But for me, at least, these words and things do not build a complete picture. For that, you must imagine. You must leap beyond the words and things to create in your mind a vanished world, calling up all that you know of this time and other times and what you think you know about humanity and the world, filling in the outlines drawn by what you can learn with what you feel must be true.
Which is why I believe there is a role for historical fiction in understanding history. If you ask me what was life like at the court of Henry VIII, my first recommendation would be Wolf Hall and Bring up the Bodies. If you want to understand the strange Viking colony on Greenland, I suggest starting with Jane Smiley's The Greenlanders. And if you want to understand Viking Britain, my new choice is Bernard Cornwell's The Last Kingdom (2004). Cornwell is not factually perfect, but to me this book both conveys the life of a noble warrior in that age better than any non-fiction work I know, and it offers a clear explanation of both why the Danes were victorious in so many battles and why they ultimately failed to hold onto what they conquered.
(The Last Kingdom has been adapted for television, but I have never seen it.)
The Last Kingdom has some problems as a novel: the plot feels contrived, some of the characters are unconvincing, and it might be the most masculine book I have ever read, with women appearing only as sex objects or strange, fey creatures beyond masculine ken. But some things about it are wonderful. The battle scenes are among the best I have read, drawing on the vocabulary of Norse and Old English poetry to convey the horror of the shield wall and the feelings of the men who stood face to face with their enemies and died or killed. On the model of Homer, Cornwell uses familiar imagery drawn from nature or home life to invoke the strange, brutal world of battle. And as I just hinted, Cornwell has delved deep into the lore of war to explain the Vikings, who were so often triumphant in battle against enemies with more men and more money but ultimately failed to hold onto their conquests.
The narrator of The Last Kingdom is a Saxon nobleman whose father was killed by the Danes when he was young, and so ended up being taken in by a Danish warlord and raised as a cross between a hostage and a foster son. He comes to admire the Danes and to love their company; they are brave and free, taking what they want by force, loyal to their friends and lords but deadly to their enemies. They seek joy in life and feel no shame in loving sex, drink, and war. Their great enemy King Alfred of Wessex, on the other hand, is surrounded by monks and prays for hours every day to be freed of sin, and Christmas at his court is a dismal affair of fasting and prayer, nothing like the drunken revelry of Danish Yule. But as the narrator passes back and forth between the two sides of this war, he comes to understand that while the Danes are close to invincible in battle, they have no plan for winning this war and completing their conquest. It is pious, sickly Alfred who has a plan, and the resources to back it up.
If you are interested in this period, or in how warriors felt and thought about war in a warrior age, I highly recommend this book. It might not be right, but to get to the heart of most things you must make a leap across the chasm of what we do not and maybe cannot know. This leap lands very well indeed.
Glory in battle!
The fight was near, the time had come
when men who were fated should fall on the field.
A great warcry arose, the ravens wheeled,
the eagle was eager for corpses; there was clamor on the earth.
– The Battle of Maldon, c. AD 991
The best summary of my thoughts on the Viking phenomenon is probably this post on the Berserks.