1892?? Wild Comanches?? Escorting a Cheyenne Chief??

Sorry, but by 1892, Comanches were long on the reservation and many were on their way to becoming successful cattlemen. (See Quanah Parker). Also, there would have been no need for a soldier to escort a Cheyenne Chief anywhere. When the Government wanted NA chiefs to go anywhere in 1892, they just hopped on a train. This SHOULD have been set in 1872 when the West was still wild. Why wasn't it?