The Viking ship was perfectly adapted to the needs of these hardy adventurers. Swift, with a draught shallow enough to enter rivers and creeks, it gave the Vikings the same advantage of mobility over their opponents and victims as the camels of the Bedouin and the ponies of the Turks did over theirs.
The name Vikings has an immediate resonance for most people in the English-speaking world. Whereas the Huns, Arabs and Mongols seem to belong to the ‘other’, remote and inaccessible in both their culture and geographical location, the image of the Vikings is clear enough. They are part of the folk memory of western culture that has been handed down from generation to generation. And what an image it is: the Viking warrior, often with his horned helmet (for which, sadly, there is no real historical evidence) stands on the shore, sword in hand, his ship pulled up on the beach behind. There is probably a burning monastery in the background and booty being carried down to the ships. In fact, of course, the reality was much more complex: Vikings as farmers, Vikings as merchants, Vikings as explorers were just as typical as Vikings as pirates.
The origins of the name Viking are obscure but the Old Norse word meant ‘fighting at sea’ while the sea raider and robber was called a Viking. People of the Viking age used many different words, Northman (or Normans), Danes, or, further east among the Slavs, Rus, another name of obscure origin. For the historian of warfare, however, the term Viking conveniently describes the extraordinarily effective fighter who dominated the northern seas and the coastlands from the end of the eighth century until around 1066.
To understand the military success of the Vikings, we must turn first to their ships because it was these which gave them the technological advantage, the Viking equivalent, so to speak, of the mounted archery of the steppe nomad. Viking ships came in many different shapes and sizes but there was a clear distinction between warships and cargo or trading ships. All Viking ships were clinker-built, with overlapping planks nailed on to a wooden framework. This style of shipbuilding became standard in northern Europe but it marked a major departure from the classical Mediterranean tradition of shipbuilding, where the planks were joined edge to edge by grooved joints and where there was no interior frame at all. The hulls were usually made of oak but pine was used for the masts and spars. The Viking method of building produced ships which were light and strong but also flexible, so that they could ride and bend with the seas. On the replica of the Gokstad ship, which was sailed across the Atlantic in 1893, it was noted that the keel would rise and fall by up to 2 em (3/4 inch)and the gunwales twist up to 15 em (6 inches) out of true.
The warships were superbly designed for their function. These were the famous longships, often called snekkja in Viking times. These could be powered both by oars and sails. The oars enabled them to operate in confined spaces or against the wind while sails made it possible for long voyages in the open sea to be undertaken. They were steered by a large oar attached on the starboard (that is, the steering-board) side to the stern. This steering-board projected below the level of the keel, to give it greater pull, but could be raised when the ship entered shallow waters. Ships would also have had iron anchors or anchors with iron flukes and wooden stocks. Fragments of anchor chains have also been found. These would allow ships to be moored away from land so the crew could rest, safe from their enemies. A reconstruction of one of the Roskilde ships has shown that it could make 9 knots under sail and 5 knots when being rowed, as fast as any vessels constructed before the age of steam. The reconstructed Gokstad ship reached 10 knots and more on its transatlantic voyage. These speeds suggest, in theory at least, that the crossing from western Denmark to eastern England could take less than forty-eight hours and the passage from Norway to Iceland could be made in three days. Of course conditions would seldom have been ideal and most voyages would have taken longer, with ships struggling against the prevailing winds and being blown off course. The passage from Denmark to England might equally have taken four days’ continuous rowing, or at least a week allowing for rest periods. Even so, these timings imply that it was not a very ambitious voyage and could be temptingly easy once news spread about the wealth of England and the lack of defences.
A second vital design feature was the very shallow draught of at least some of these ships. The same Roskilde ship had a draught of no more than 18 inches when fully laden. Because of the design of the hull and the keel, this seems to have been achieved without any loss of stability. It enabled them to bring their ships right up rivers such as the Loire, which were much too shallow and filled with sand-bars to allow more conventional navigation. They may also have been able to escape from pursuit by larger vessels by skimming through shallow waters.
As might be expected, the ships varied greatly in size. The small warship reconstructed on the basis of the Roskilde finds was 57 feet long and 8 feet wide. It carried a crew of twenty-six oarsmen and there may also have been a captain or steersman on board. Another of the Roskilde ships, not so well preserved, was much larger, probably just under 100 feet long and 13 feet wide. By analogy, it might have had spaces for fifty oarsmen. The Gokstad ship had spaces for sixteen oarsmen on each side and the coloured shields they attached to the outside of the boat were recovered in its excavation. In all these cases the numbers of oarsmen may have been supplemented by other warriors.
Ships were often described according to the number of oarsmen they could hold. The smallest ships were so narrow that one man could hold two oars, one on each side. Larger ships were described by the number of benches they carried for two oarsmen. The standard ship specified in ship-levies was the twenty bencher, i.e. forty oarsmen, but ships of up to thirty benches are recorded.