The swords of the Norse are among the most iconic in history. Among students of arms they continual to be one of the most popular weapon forms of the West...and for good reason. There is no denying their austere beauty, originality, and technical quality. But there are aspects to them not generally considered. We have to ask not only why did they originate but what happened to them? Viking swords owe a debt to their earlier cousins among the blades of Dark Age "barbarian" tribes. But they soon came into their own, both functionally and aesthetically. It's easy to grasp how a culture that emphasized the prowess of the individual warrior fighting almost, but not entirely, on foot in tribal skirmish and feuding clans, would come to favor a particular type of fighting blade. They would naturally gravitate toward a beefy yet elegant sword useful in both single combat or clash of short battle over one fit for large formations of trained soldiers on campaign.
They would need one practical for a shipboard encounter, shield-wall defense, rural raid, or sudden personal assault. They would need one that could deal with targets wearing more than just thick furs and leathers as well as the increasingly effective defense offered by chainmail. They would need a weapon that could whip around to strongly chop and slash at a large opponent adroitly wielding an agile wooden shield as much as the cleaving blows of an agile battle-axe. It would need a cross-section that was flexible and resilient to withstand beating against hafted weapons and warding off blows, yet robust enough to deliver shearing cuts on flesh and bone. Such a sword would require a grip that allowed the single hand to hold on snugly while still providing maximum suppleness to the wrist. All these elements and more were achieved in the swords of the Vikings. Surprisingly, aside from a few lines in the Sagas, virtually all we actually know about the properties of Norse swords comes almost entirely from examination of a small quantity of surviving specimens of generally poor condition and experiments with modern replicas of these examples.
There simply isn't the body of literature and artwork about them that exists for the swords of later centuries and other cultures. Nonetheless, what we do know is that there were regional differences among Norse swords even as there was a mutual influence between them and those from elsewhere in Europe. Curiously, on top of this, the distinction between Viking sword blades and those used by the AngloSaxons and even the Franks are not all that great. Yet, it is Norse swords which have come to stand out. To see the larger picture, merely consider that all sword designs and their manner of construction are a compromise. They are a trade off between the limitations of the maker's ability to work available materials and the technical demands of their function as a lethal weapon. It's a life-and-death matter of being effective in the different kinds of offensive and defensive actions they can perform contrasted with their sharpness, toughness, and resilience. Achieving an aesthetic harmony in these elements is surely what defines the best swords.
Though, keep in mind, in earlier ages a sword was crafted by a smith only in relatively small quantities through considerable labor and cost. Such a prized tool would be well-decorated, well-kept and, because the mysteries of metallurgical science were still unknown, always considered with a certain awe. To the fighting man, it was a matter of practical survival (along with a certain mysticism), and Viking swords in particular were emblematic of all this. Yet, when examined in this context, the deeper reality is that the Vikings did not face an especially wide array of particular enemies for which their swords proved decidedly effective over others. And in time, they were supplanted by newer knightly arming swords even as the Norse themselves supplanted their older faith and culture with that of Christendom. Eventually, their indigenous sword style was overshadowed by a slightly tapering design with a somewhat thicker cross-section that enabled a more versatile action from cut to thrust and back again against thick metal-rimmed shields and the more resistant armors coming into use.
As effective on foot as on horseback, with a cruciform hilt adapted for agile use in either one or two hands, the classic Medieval sword was born. These newer swords with strong biting edges and generally more narrower points were at least as deadly and reliable. They proved effective against different armor designs while being balanced for use by fighters wearing such in combat. Their hilt style also provided these blades the necessary maneuverability to fight against a host of adversaries amidst clashing armies on campaign, fortress sieges, and knightly judicial combats. It's possible their method of forging may even have been significantly less intensive. Just as Viking ships served out their utility until newer designs and maritime eventually rendered them unnecessary, the age of the Vikings also ended...and so did their traditional sword. But their heroic, albeit sometimes brutal, allure cannot be denied. That the renown these very personal weapons earned is due as much to the ferocity and tenacity of the tales surrounding their users, as well as the distinctive beauty of their form, its part of their lore. They earned their niche in martial history and no student of the subject can overlook their importance nor consider themselves informed without deeply exploring these proud entries in the world of fighting blades.