Glad you enjoyed it! I learned about them through Golden Kamuy, the anime/manga the pic is sourced from. It went into some basics of their culture and the background of who they are, where they came from, and explored the point in time where they started to be forced to assimilate into Japanese culture.

From the tattoos, the spirits of gods inhabiting animals to visit with them, to fish skin clothing, beautiful artwork, reindeer farming, foods, and environmentalism, I’ve read a bit about them. They still face a lot of racism today and many hide their heritage, but that is slowly starting to change.