The Victorians were fond of the Vikings. In 1869, the year that the Cutty Sark was launched, R.M. Ballantyne published a popular novel called Erling the Bold: a Tale of the Norse Sea Kings, which drew heavily on the Icelandic sagas of the Scandinavian peoples who lived in northern Europe during much of the early Middle Ages. In its preface he wrote: “Very much of the religious, civil, and political liberty which we enjoy at the present time — the liberty of the press, freedom of speech, the influence of public opinion over public affairs and many of our cherished institutions . . . in short, the spirit of the age and the germs of the British Constitution — may be traced to the Norsemen of old; those sturdy Vikings . . . who marauded, conquered and settled in this country at various times between the 5th and the 11th centuries.”

This was romantic cobblers, designed to please patriotic schoolboys. But there was plenty of it around. The Vikings were regularly portrayed as a lusty, seafaring nation whose hearty interest in colonising other countries was tempered with an earthy sense of fair play. Or, in 19th-century terms, the sort of ancestor worth having.

Times change. These days, the Vikings have been relegated to the second tier of civilisations worth raving about. (One BBC bigwig recently told me that the only TV history worth commissioning is on “dinosaurs, Egyptians, Romans and Nazis”.) Their deeds seem either cartoonish or obscure; if most people have any knowledge of them at all, it is the peculiar smell remembered from childhood visits to the Jorvik Viking Centre in York.

So let’s refresh. The people we call the Vikings originated as polytheistic heathens from Scandinavia between the 8th and 12th centuries. Their name evokes a seabound wandering, with warmaking, settlement and piracy all implied. They wandered westward to Greenland and the fringes of America, and eastward to the Baltic and Russia. They raided and settled in Ireland and in southern Italy. They threatened the post-Carolingian Frankish kingdom along its coast, over land, and even with raids up the Seine. They encountered the Muslim people in the Spanish peninsula and North Africa.

Their earliest contact with Britain came in 793, when they landed amid violent storms at the great monastery on Lindisfarne. The monks there may have had as little as an hour’s notice of their arrival. When they touched land there was no reckoning with them.

A 12th-century chronicle described the raid: “The pagans from the northern regions came . . . like stinging hornets . . . and slaughtered not only beasts of burden, sheep and oxen, but even priests and deacons, and companies of monks and nuns. [They] laid ] everything waste with grievous plundering, trampled the holy places with polluted steps, dug up the altars and seized all of the treasure of the holy church. They killed some of the brothers, took some away with them in fetters . . . some they drowned in the sea.”

It is a violent picture, and it is with violence that the Vikings are frequently associated. War, trial by ordeal, slave-taking and animal and human sacrifice were integral to their culture. Yet beneath this was a complex heathen spiritualism, which gave way by the end of the Viking age to a generally adopted Christianity.

This change from heathendom to Christendom is the chief concern of Robert Ferguson’s new history of the Vikings. Thor’s hammer and Christ’s cross bear obvious structural similarities and, during the 400 years covered by Ferguson’s intricate and thoughtful work, the two gradually dissolve into one another.

Ferguson’s main achievement in this book is not to throw the seafaring baby out with the salty bathwater. In revising the credulous mumbo-jumbo celebrated by the Victorians, the temptation must have been to disregard most of what is written in the sagas and chronicles on the grounds that they were written either centuries after the events they describe, or else from the perspective of those who had quaked before the prow of a longboat as the cow-pie helmets hove into view.

This temptation is admirably resisted. Rather than being sceptically dismissed, the narrative sources are cross-examined against extensive archaeological, genetic and physical sources. Runes, ships and relics are key witnesses in decoding the quasi-mythical stories about heroes whom Ferguson accepts from the outset we can never truly know. In maintaining some semblance of narrative thread, Ferguson says he has had to make certain “concessions to the idiom of legend”, but the judgment he exercises in doing so seems to me pitch-perfect.

And so we have heroes and villains restored tentatively to life. There is a noble attempt to delineate men such as Ragnar Hairy-Breeches, Ivar the Boneless and Harald Bluetooth from the myths that have subsequently become them. The journey from hammer to cross, undertaken under the auspices of these men, their ancestors and contemporaries, is a fascinating one. And if occasionally the story feels fragmented and the cast of characters weak, it is because we are following a historian picking his way through a mist destined never fully to lift.

But why should we still care about the Vikings? Unlike the Victorians, we now have little instinctively in common with our Scandinavian cousins, save perhaps a fondness for binge-drinking, Ikea furniture and — if Michael Gove gets his way — state-devolved secondary education.

Perhaps it is because Ferguson’s book shows us our present de-Christianisation in reverse. As Europe slinks back into heathendom after a millennium of relative godliness, now is a good time to consider how our hairy-breeched ancestors got us where we are; and what it is we are now leaving behind.

The Hammer and the Cross: A New History of the Vikings by Robert Ferguson
Alan Lane, £30; 480pp Buy the book

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