But not only is it legal to openly carry a sheathed sword, it's the law. Any kind of concealment for bladed weapons is a misdemeanor. Bladed weapons in most states where they are legal to carry, are usually illegal if they're longer than five inches. Concealed blades, like cane swords, are always illegal.
Swords come in many shapes and sizes, but most are considered "bladed weapons" under the law.
And like their shorter cousins -- knives -- swords typically fall under state laws prohibiting the carrying of bladed weapons over a certain length. However, the law can be different depending on whether the blade is sheathed. Here are a few state examples:
In California, anything with a fixed blade (like a sword) must be worn in plain view. But sheathed knives worn openly are not considered illegal concealed weapons. However, if you're carrying a cane sword, you can be charged with a misdemeanor.
In Texas, illegal knives are described as knives with blades longer than 5.5 inches, along with swords. Still, swords are legal to carry if they are being used in historical demonstrations or ceremonies in which the sword is "significant to the performance of the ceremony."
In New York, possession of a cane sword is a misdemeanor, but it can become a felony if it is a sword-carrier's second or third offense.
Federal law has similar prohibitions about carrying bladed weapons in public, although you may be able to pack a sword in your checked luggage if you follow the rules.
PLEASE CHECK YOUR STATES LAWS ON CARRYING A SWORD!