Its a good movie, but don't go into it thinking it's amazing. I enjoyed the movie and the director is considered one of the last masters of Japanese cinema. This movie is one of his lasts yet never received much recognition. There always political social narratives in the mix of these types of movies. I hope you can get something out of it.
There a few movies that have recently (in the last 15 years) that have been on Hokikdo because the internet has made the Ainu some of the most popular searched subjects in the world, thus putting pressure on the Japanese government to treat them better and become a possible money maker for Japan's mass media, like in music and movies.
Another popular one online seems to be "Ungorgiven" (2013) and "Year one in the North" (2005). These are possibly superior movies in terms of budget and advertising to the general public.
Poppoya (1999) is out there.
The oldest movie on Hokido I know of is Abashiri Prison from 1965 where The block buster star Ken Takakura essentially his debut launching his career where they made 10 more sequels for he movie. It's a prison break movie. Its almost an essential to any Japanese film buff given its impact on Japanese cinema both short and long term.
There's plenty of more movies on Hokikdo floating around doing a simple internet search, but these are the most notable. The Ainu are still a people's seen as second class citizens in Japan despite most people thinking they're deserving of respect from the younger generation in Japan. The problem is no.one wants to given them ancestral lands or allow them to participate in their traditional recorations or ceremoneys, like stuff as simple as hunting elk with bows or fishing. The elders and youth still want to do these things while maintaining much of modern lifestyle, but Japan won't allow it.
That's why its a bit hard to have these movies produced. They go almost 10 years without a movie on Hokido being produced.
I've got serveral places picked out to visit in Hokikdo if I can visit one day. I even looked into finding a university in Hokkido to see of they would or have ever done am archeological search on specific portion of a a semi famous lake island. I never got around to it. One project at a time, else.nothing will get done.