There are really so many swords. For more than 3000 years the variety and diversity of hilted long-blade hand weapons around the globe has been enormous. Their specialization bore witness to more experimentation and personalization than any (non-firearm) weapon. Whether as pragmatic tools of war, protective side-arm, or the preferred means for defending personal honor in duel, the sword has ever been the most regarded of weapons. The story is a complex one of adaptation and innovation melded to pragmatic function and proven tradition. It shouldn't really be a surprise then that there are so many different kinds of them.
In the Bronze Age the earliest long-bladed knives proved their worth in slashing, chopping, and stabbing against clubs, axe, spear, and shield. But it was the Greek's who achieved success with shapes ideal for skillful use by their hoplites in battle and single-combat. Their xiphos and falcata perhaps first allowed the merging of functional form to swordsman's skill. The Romans advanced their short-sword forms to meet the needs of both the legionnaire in close formation and the gladiator in bloody public spectacle. The gladius won them an empire. Both cultures also employed curved blades with their mounted troops and these survived to become the swords of the Byzantine cavalry that successfully defended the West for centuries. The fusion of such expertise with the metallurgical achievements of Celtic, Germanic, and Anglo-Saxon styles produced still larger sword forms in Western Europe. Perhaps none were as feared and admired as those of the Norse. As with any other weapon, the Viking sword evolved to answer the demands of the martial environment they faced. But few have proven better against coats of riveted chain-net armor and hardened leathers. They were quick, able, and reliable swords for the individual warrior in sea-borne skirmish, man-to-man combat, and the clash of shield-walls.
But even these were eclipsed by Europe's new feudal Milites wielding swords developed to maximize the formidable power of the heavily armored Medieval horseman. A wide, double-bladed cruciform-hilted arming sword became the premier weapon of the Chivalric warrior. Even this was just one among a family of similar swords, differing tremendously in width, length, taper, and shape as well as grip. Medieval close-combat varied to such a degree that short, tapering arming swords were employed by men-at-arms as much as the larger double handed warswords and everything in between. Narrow, stiff, straight swords with square or triangular blades perfected for puncturing armor existed side-by-side with extra-wide curved ones of single-edge formed to deliver fearsome shearing blows. Such tucks and falchions were still in use even as knightly plate-armor perfected its form to near invulnerability to anything but guns. But it was the agile and powerful knightly longsword that proved to be one of the most versatile forms ever produced. Finding proven use for some three-hundred years, it was produced in near countless forms and was literally carried into all manner of combat encounters around the globe.
As military technology improved and older methods of warfare evolved, giving way to the dynamic battlefields of the Renaissance, two-handed great-swords were developed with enormous blade shapes fitted to a near-endless array of hilt styles. At the same time, the older arming sword narrowed and lengthened into a new "cut-and thrust" form better suited as a single-hand side-arm for urban frays and common street fight. While never completely disappearing from military use, such side-swords evolved into an entirely new civilian sword. Intentionally designed for unarmored single-combat and private duel of honor, the long, thin rapier with its unique "foyning fence" became synonymous with the gentleman cavalier and swashbuckling duelist. Deceptively agile and blindingly quick with extraordinary reach, it's thrust came to be respected. Surely, no other sword form in history appeared as suddenly to dominate a niche so completely only to then quickly fade as did the rapier.
Changing social customs eventually rendered the long rapier as impractical for personal self-defense as the Medieval swords had themselves become obsolete for war. Within a few generations Baroque gentleman resorted to a smaller, nimbler version of the rapier adapted solely to the stylized idiosyncrasies of aristocratic dueling culture. This smallsword eventually become the foundation for the civilianized play of modern sport fencing. By contrast, with no requirement to any longer overcome armors or outfight an immense array of weapons in the manner of their Medieval and Renaissance forebears, military swords in the West regressed to a handful of simple cavalry sabers and cutlasses. Such "modern era" swords were mass produced in near endless blade curvatures, widths, and hilt configurations having only the barest connection to the long established forms of earlier ages.
Though less known and respected in the West, for centuries Turkish and Indo-Persian swords distinguished themselves in form and function as much as did their Western cousins. Their differentiation into designs suited to armored or unarmored fighting and foot or mounted combat was just as wide-ranging. They proved equally capable in almost all respects. While the traditional swords of China are invariably represented today by a mere pair of better-known, yet simple, cut and thrust designs, their history is almost as rich and complex as their European and Asian counter-parts. Yet, surely no swords in history have been as widely promoted (and hyped) in the modern era as those of Feudal Japan. Viewed in perspective and context, they are unarguably distinct and effective forms; technological and artistic marvels perfected for the challenges of their own martial milieu. Yet, as with any other man-made fighting blade, they exist with their own particular set of functional compromises and design limitations.
Whatever the form, real swords were always achievements of technological know-how. Swords were the work of craftsmen who merged hand-wrought steel with artistry to meet the violent needs of fighting men. Not all swords were as capable or versatile, not all were as strong or sharp, nor were all as aesthetically impressive, but each was deadly in it's own right. The distinction among sword types throughout history is testament not only to the practical effectiveness but also the ingenuity of their designs. Each is embellished by history, heritage, legend and lore. Whether intrigued by their craftsmanship and artistry or inspired by performance of their deadly utility, people have for ages come to be fascinated by so many swords.