History of ninja swords. Ninjato. Ninja weapons. Sword history.
The highly skilled covert agents or mercenaries of Feudal Japan, the ninja, are cloaked in mystery. Very few documents exist to divulge the details of these soldiers, how they worked, the weapons they used and similar. As a result the actual weaponry used by the ninja is open to speculation. It is highly likely the ninja used a normal Katana, as would the much more ordered Samurai soldiers of the period.
Modern media has invented a different sword for the ninja; the short, straight bladed Ninjato. This weapon was single edged and one-handed. Opinions vary on the use of the weapon, but it is commonly accepted that the underhand hold (where the blade extends downwards from the hand rather than upwards) would result in a less firm grip and was never used. In fact, the Ninjato is an invention of Hollywood and never existed.
Ninja would reputedly use their Katana as much more than a simple sword. The long blade, when sheathed, could be used to probe for traps, and the sword itself could be rested against a sheer wall so that the sword guard could be used as an ad hoc foothold to aid scaling the wall. Also, it is thought that some ninja may have put a concoction of red pepper, dust and iron filings near the top of the scabbard so that when the sword was drawn the powder would fly into the enemy’s eyes, stunning him so that a lethal strike could be made.