I'm gobsmacked. I'm a native Sooner...and I get corrected by a Volunteer.
But the Osage Reservation (Osage County) has to be the oddest Indian reservation in the country. Of the 47-some thousand folks living in the county, 66% are white, 11% are black...and only 14% are Native American.
I've been to Osage County numerous times and was never aware that it was still a reservation. Nor did any of the folks from Osage County that I knew ever mention it.
I'm pretty sure the county government is separate and independent from the tribe, though.
I’ve been in Osage, too. Unfortunately had to rush through it en route to Bartlesville (spent the night in Frank Lloyd Wright’s Price Tower). Pawhuska, the county seat, clearly had its glory days back during the early 20th century Oil Boom, most of the buildings dating from that time. I hope to get back there some day to photograph it.
You’re right about the demographics. I think a lot of the natives may have left. It has nearly 50k people, but it also did back around 80 years ago only to empty out down to below 30k. Osage extends all the way down to within sight of Downtown Tulsa and part of the county, I believe, has been annexed into it, which could account for the population growth again.
I’m not sure of the political divisions in the county with respect to tribal government. Given that the county and Osage Nation are considered contiguous according to the maps, it may be one in the same.