Graham Greene's Dying Wish Was to Thank Kevin Costner for Native People Representation

One of Graham Greene's dying wishes was to get in contact with Kevin Costner -- but he was unable to, TMZ has learned.

The late actor's rep Michael Greene tells TMZ ... he wanted to speak with Kevin to thank him for the representation he gave native people in media over the years. His team tried their best, but were unsuccessful.

However, the "Yellowstone" star paid tribute to Graham on social media Tuesday, one day after he passed in a hospital with his wife, Hilary, by his side.

Check out KC's post ... he shared a scene from their 1990 film "Dances With Wolves" as he remembered his costar as a "master at work and a wonderful human being" who was able to "establish so much about the relationship between Dunbar and the natives with so few words" in the scene.

As you know, Kevin has long given indigenous stories a platform through several major projects. Graham's breakthrough role was Kicking Bird in "Dances With Wolves" -- a role that earned him an Academy Award nomination for Best Supporting Actor. The Western follows a Civil War soldier who develops a deep relationship with a Sioux tribe and integrates with them.

Graham died Monday at 4:02 PM after a "lengthy illness," his rep told TMZ.

Greene also says Graham wanted the world to know he "had a great life" and "discovered so much," and he looked forward to discovering more once he transitioned.

He was 73.