Looks like a late victorian era "Gentlemen's chair". Likely walnut dating 1890 through maybe 1910. Part of a parlor set which included things like gentleman's chair, lady's chair, side table, settee perhaps a rocker and maybe even a corner chair.

Do come back and let us know what you find out? Perhaps send your pics to the company that distributed it, and maybe someone there can tell you when it was made. When I saw mine on Craigslist, I HAD to have it, after I researched it. I don't have gout, but thought it was just so unusual. Mine was used by the elderly seller's great grandfather. I bought it last year, and it's a great conversation piece. Most people today haven't heard of them. I pulled the info just below from this - FURNISHINGS : History’s Been Putting Up With Footstools The article is from the LA Times, written in May 1994. "By the 17th Century, the footstool concept had trickled down to the common everyday rich folk in the form of a “gout stool.” Then, gout was considered a rich man’s ailment. The gout stool was a means of elevating throbbing feet for relief and protection." I just found this, which is VERY close to mine, although not in great shape. I don't have a Worthpoint account to see what it sold for - https://www.worthpoint.com/worthopedia/antique-gout-stool-rocking-chair-rare-1800-wood Here's a video on one - https://www.youtube.com/watch?v=0LAum-_bbGQ

If you look at old chairs with wood seats, they almost always have at least some type of contouring on the seats. Yours are so rustic, including the backs - except for the piece in the middle, they almost look like someone cobbled together a couple of different sets making repairs or partially home made them and put those seats on. It looks like you can see nails where the center of the back was nailed to the cross piece. Unless you plan on restoring them, I wouldn't feel bad about separating them, but if anyone is interested in buying them, you might have better luck selling all 6 and buying 2 comfortable ones for yourself. They look like they've been left out in the weather, or lived through a flood?

The upholstery looks new and looks like polyester. Of course, from a pic, it's hard to tell. You can remove the cloth on the bottom of the chair and see if there are any markings. That was an expensive chair, so when it was originally upholstered, it did not have straw. Older chairs had horsehair, but that was always covered with cotton or polyester batting. Horsehair is now quite expensive, so I've see straw used. If the straw had been there for a while, it would have softened.