In Japan lies a unique sword: the Norimitsu Ōdachi. This special sword is incredibly long - over 3 and 3-quarter metres. While some have speculated it was made for a giant, others have posited more likely, though mundane purposes.
What is an Ōdachi?
An Ōdachi is a big Tachi. To be considered an Ōdachi, the blade needs to be over 3 shaku (90cm). While the extent of their use in battle is unknown, we do know they were used in ceremonies, as symbols of status, and as offerings to gods. To learn more about Odachi in general, please see our related blog post: The Japanese Greatsword: The Ōdachi .
Why Is This One So Large?
The original purpose of the Norimitsu Ōdachi has been lost to time, but we can conclude a few things. The first is that it is too large to have been used for battle in any practical manner, as at 14.5kg, it is just too heavy. (For comparison, a traditionally-made Katana weighs around 1.7kg). Thus, it was likely used for ceremonial or religious purposes. There is one other possibility - it may have been made as a status symbol.
Making swords is not something that can be learned in an afternoon. To forge a sword, iron ore must be heated and the impurities removed. Then the ore must be sorted based on carbon content, heated, hammered into a blade, heated again, clay hand-applied, then quenched. Each step in this process allows little to no room for error without destroying or irreparably damaging the sword. And remember, they didn't have modern electronic equipment or power tools to assist them - they had to do it all by naked eye and by hand.
This difficulty compounds the longer the sword is. The more metal there is, the more likely part of it won't be heated to the right temperature or have all of its impurities removed. This is without taking into account the bigger equipment and facilities needed to house the bigger blade (swords are made as one piece - they can't be made piecemeal). Thus only an expert swordsmith could even hope to make an Ōdachi, and only a wealthy person could pay to have it made.
Thus, regardless of whether it was commissioned by a wealthy individual or made as a showpiece by the swordsmith himself, there is no doubt it would have served as a powerful status symbol for whomever made it or owned it (even if it were made as a gift or offering). Today, though, it merely serves to impress any of us fortunate enough to see it.