Interesting question! I did solve it, but here was my process...
I cropped out your close-up insert and uploaded it to tineye.com. That is my go-to reverse image search, but this time it didn't come up with anything. Then I tried duplichecker.com which links to six reverse image search sites. The two on the right, which are yandex.com and graph.baidu.com, both seem to think it's a video game map, with the latter pulling up many images of Super Mario Bros., Milon's Secret Castle, and other games with bricks and sky.
I looked again and I doubted that it's a game map. The colored rectangles didn't look like game tiles. For a second I thought they were flags. But flags don't really look more vertical than horizontal. Banners maybe? Then I thought they might have been coats of arms, like European families have. I Googled "maps with coats of arms" and this came up:
So it turns out, it's a map of Ireland. The Heraldic Scroll & Map of Family Names & Origins of Ireland, to be precise. If you like it, you can
buy a puzzle version of it.
Well, that was a fun search. Good to have solved it, I hate it when mysteries don't get solved...