Who was the first that forged the deadly blade? Of rugged steel his savage soul was made - Tibullus
For such a ubiquitous piece of kit, a sword is a remarkably hard thing to define - we can say for certain that it is a bladed weapon made of metal, but beyond that things become hazy. In general a sword will consist of a blade (the damage dealing part), a hilt (the handle) and a crossguard (between the two).
How long should the blade be? When does a blade become too big for a dagger and become a shortsword (or, indeed, a regular sword)? Just how long is a longsword? The answer will vary, depending on your era and culture - and very probably upon the metallurgical skills and fighting doctrine of the wielder. Anything shorter than a couple of feet (about 60cm) is probably a shortsword at best.
How many cutting edges should the blade have, and should they be straight or curved? Some cultures prefer a single cutting edge, others a double edged weapon and in some cases there have been things called swords with no cutting edge at all but a sharp point for thrusting. Sharp edged swords may or may not have a stabbing point. Curvature of the blade is also culturally dependant. The sabre, scimitar and katana are all curved, single edged swords, whereas most medieval European swords are straight, double edged blades - consideration will show that a curved, double edged blade is probably a waste of the swordsmith's time. Either kind may be made with or without a stabbing point but a rapier or an estoc would be an example of a point-only blade.
How many hands should the weapon be operated by and how long should the handle be? Again, this is a cultural question - some swords are designed to be used with one hand, others with two and some can be used with one or two hands and the length of the hilt will vary accordingly but when a long handled sword becomes a short handled glaive is a matter of opinion. Even when a sword is known to be operated with two hands, where the hands are put can vary - most late era two handed swords feature a foregrip on the ricasso1 to which the user can move a hand so as to grip the sword for more efficient thrusting. Whether weapons like the falx and rhompia are best classified as swords, glaives or some other category remains debatable.
We can say for sure that the earliest sword-like weapons seem to occur about 3300 BC in central Anatolia, but these don't seem to lead to anything very swordlike until the late bronze age due the difficulty of forging any blade longer than a couple of feet in early bronzes. Swords, in one form or another, have been with us ever since, but most sources will agree that a good sword needs to be made of steel. If a better choice of metal exists, it has yet to be discovered.
Also - and for reference - the longitudinal groove (or in some cases grooves) found on some sword blades is not a "blood groove" as the Victorians seem to have persuaded themselves, nor does it have any function in making the sword easier to pull out of your opponent if you manage to get it stuck in them (another apparently common myth). It's called a fuller (after the tool used to construct it) and its purpose is to lighten the blade, allowing a larger weapon to be made with the same mass of metal, working in a similar manner to an I-beam in structural engineering.
The sword is, typically a versatile weapon but relatively expensive and hard to use well - in many places it has been the mark of the professional fighting man and/or the aristocrat whilst the levy or common soldier was armed with a spear or, in later eras, a firearm. Certainly the sword, unlike most other weapons, is entirely without civilian applications and is purely a weapon, and that alone may be enough to give it a unique character.
Extremely well-made swords — especially ones associated with famous heroes or great deeds — may acquire names. Famous swords of fantasy include King Arthur's Excalibur and Gandalf's Glamdring. In the real world, the mysterious Ulfbert swords appear to have had a significant reputation in the "Viking" era2. As high status items, swords are generally ahead of the curve when it comes to being made into magical weapons - indeed, it's relatively rare for a sword using culture to spawn any other kind of legendary magical weapon3.
The sword also has some significance in the practice of ritual magic - in some traditions it serves as a group aspect of the athame, attuned to the element of fire and representing the "male principle" as the "spear counterpart" of the cauldron.
Besides magical ritual, the sword can also be used as a symbol of temporal authority and/or military command - partly due to its associations with "professional warrior" status and partly as a syndoche for armed force in general - and thus ceremonial swords may well be paraded before or flourished by rulers on state occasions. The sword may also symbolise the authority to punish (thus taking the same role as the axe in the Roman fasces) - and this may be taken to its logical conclusion in the Executioner's Sword.
Game and Story Use
- Most RPGs make swords unrealistically heavy and cheap and seem to regard them as entry level weapons. They should be none of these things.
- Arguably a sword that was as heavy as one in many RPG rule sets could be fairly cheap, but only because it would be very nearly unusable.