I don’t really know what this garment is called. The pattern envelope (McCall’s M7525) doesn’t call it anything; it just has a picture of the garment, and inside are instructions on how to make it. So I did. It comes with a pair of pants that are effectively hakama pants, even though they don’t have the exact right form of hakama.
So this is effectively a short yukata, or tie-front tunic similar to the kimono but of less formal (i.e., cotton not silk) fabric and cut. It appears to be put together correctly.
In general, Japanese traditional garments and similar styles are very “Dark Ages” in feel. They’re not assembled the same way as Viking or Anglo-Saxon clothing of the sixth and 5th century AD… but they ARE made up of simple pieces of fabric with only minimal changes in shape from what might come off the loom (which is to say, mostly squares and triangles). Each sleeve is merely a long rectangle. The back is really two large/long rectangles sewn together. The band around the neck and across the opening’s edges is two long rectangles. The two ties to hold the garment shut are long rectangles folded and sewn together. The two front panels are the only non-rectangles… Except that they sort of are rectangles — truncated across the top on opposite sides. Rectangles, rectangles everywhere.
When I compare this with some of the mid-18th century clothes that I’ve been making recently, I’m struck by the differences. Enlightenment-era Europeans had more cloth, thanks to the Industrial Revolution, than almost anyone else on the planet could produce. The result was an emergent diversity of forms, pieced garments, a diversity of dyes, corsetry, and elaborate designs. By contrast, most of the world’s “traditional garments” are made of blocky bits more or less direct from the loom that the culture possesses — clothes were effectively woven to the right shapes, and then assembled using a minimum of technique or specialized shaping with scissors. That’s my impression, anyway — and it makes me wonder about the future, and how we’ll dress ourselves. It may be that a return to more traditional garments composed of squares and triangles and rectangles, makes a fair bit of sense.
That appears to be either a jinbei (https://en.wikipedia.org/wiki/Jinbei), or a samue (https://en.wikipedia.org/wiki/Samue).