Owner and manufacturer of katana sought

Hi, my name is Wes, and I'm trying to figure out exactly who on just Katana, and who made it I will post some pictures. Please will anybody help me decipher? Thank you.

Also it's a military katana and I beleave the owner was a captain

Sword says

井上真改 Inoue Shinkai (name, family name INOUE)
延寶八年二月日 February 1680

Many fakes out there. Proceed with caution.

Thank you what do you think would be my next step?

Forget about trying to reunite it with its owner unless it comes with some kind of provenance. Without any provenance or documentation, there is no way to find the last owner. I respect the intention, but its impossible, even with a forensic examination of the sword and quantum computing.

If you want to find out if the sword is genuine or not, the best place to go is the Nihonto Message Board. Those guys there look at swords every day. You will need pictures of the sword, not just of the tang. The mountings are not so interesting, as they don't tell us anything about the sword blade inside. If you want to know if the mountings are genuine WW2 mountings, you can photograph them as well and post them if you like, but the real value/interest is in the sword inside, especially if its an old sword. Often people post a picture of the scabbard, and say "tell me about my sword", which is like taking a picture of a frame and saying, "tell me about my painting".

Inoue Shinkai is one of the masters of the latter sword period (shintō - or "new sword" period). Since his swords are very valuable, many people try to fake them. If you look on the internet for Inoue Shinkai, you will get a lot of hits.

You are of course welcome to post pictures of the blade here as well, and I can give my own, amateur, opinion.

Thank you I was confused about the characters on tang. I knew one side was the maker I thought the others idea was the owners name

Ok well here is the sword

Need to focus on the sword. Forget about the fittings for now. This means take the sword out of the handle, and put it on a flat surface. A monochrome surface would be good. Black is usually best, but the trick is to get your camera to focus on the sword. Need close-ups of the tip and the steel so we can see the grain and what kind of steel structures there are. Important not to touch your sword with your bare hands because you will leave fingerprints on the sword which will rust amazingly quickly. Microfiber cloths are the best, but really a handkerchief or even kleenex will do.

To see the kind of photography that is the best, look at the link here. I wouldn't expect you to get this level of quality, but I'm just showing what kind of photos most sword collectors like to see.

Scroll to the middle of the page to see the individual photos of the sword. Zoom in on the photos to see close-ups of the steel, etc. The sword on that site is a genuine Inoue Shinkai sword, so in order to judge your sword properly we'd need to see a lot more detail.