Why did the United States government give Plenty Coups his own flag?

The United States government grew to respect Chief Plenty Coups' skill as a leader. They invited him to ceremonies and parades to represent the Indian people. They even awarded him with his own flag. Plenty Coups' first visit to Washington D.C. was in 1879 as part of a treaty delegation. After that, he visited Washington D.C. on approximately 5 or 10 occasions. He went to many different parades and fairs and gatherings where he represented the Indian people.
In 1905, the United States government felt that he ought to have his own flag. He was therefore awarded a flag which he used for many years at the various ceremonies that he attended. On the flag, there were 13 stars, depicting the original 13 clans of the Crow Indian people. Also imprinted on the flag were a chickadee and an eagle, two of Plenty Coups' visionary animal spirits. Plenty Coups told the government officials what things were important to him, and they translated what he had told them to create the flag. From: Chief Plenty Coups State Park Museum Tour Content
The flag is registered and recognized and has been passed down like a lot of Plenty Coups' artifacts, such has his pipe, his war bonnet and his coups stick. My father is the one that last had the original flag. He, in turn, donated it to the Smithsonian Institute in Washington D.C. where a lot of people would see it and where it would remain a lot longer than if we maintained it. We still ask them to bring it out for some occasions. From: Vincent Goes Ahead, Jr., Museum Interpreter, Vice Chairman of the Crow Tribe