Magic sword

A magic sword is any mythological or fictional sword imbued with magical power to increase its strength or grant it other supernatural qualities. The archetype originated in myth and legend, and occurs regularly in fantasy fiction.

Renowned swords appear in the folklore of every nation that used swords. Sometimes the sword is ascribed no powers of its own. It is famous because it is the hero's sword, or because of its origin, as when a god gives it to the hero. Other swords keep their wielders safe or destroy their enemies.

A more localized motif is the sword that has been broken and must be reforged, commonly found in Northern Europe. Such a sword symbolizes the initial defeat and loss of honor of its wielder. Subsequent victory and the restoration of honor is achieved by reforging it, either at the wielder's hand or that of his heir.

It is probable that the roots of the sentient weapon myths stem from ancient peoples belief that sword making and metallurgy was in fact a magical process. Through the fires of the forge (fire was also given spiritual connotations) a lump of earth was transformed into a shiny usable object that could be hammered into many shapes. Extending further from the transformation of ore into metal, the difficulty of actually obtaining a quality blade; which took intense concentration and skill added to its esoteric qualities. While any blacksmith could manufacture a knife or an axehead only a swordsmith could create a high quality sword. The secrets of doing so were jealously guarded as well as formulas for alloys.

The skill necessary to forge a balanced blade - one which is not too brittle or too soft and able to hold a usefully sharp edge - in the age before automated machines, blast furnaces, and the knowledge of molecular chemistry made the creation of a sword seem almost miraculous. A few degrees too hot or too cold within a very limited temperature range, which could only be discerned by the glowing hue of a hot , could make or break a sword. A lack of expertise in knowing when and how to apply carbon and flux and quench the blade could ruin weeks of work. Thus the swordsmith almost felt like he was one with his work, giving the process his complete devotion of concentration and thought. This led to the belief that he was actually the blade with an essence of his spirit. In Japan, the swordsmiths were so concerned with this belief that they would undergo purification rituals and meditation before even attempting to start a new blade, for fear that they might inadvertently create an evil sword.

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Wikipedia