Mount Rushmore still disputed on the basis of the 1868 Treaty of Fort Laramie (see section "Controversy" below). Among American settlers, the peak was known variously as Cougar Mountain, Sugarloaf Mountain, Slaughterhouse Mountain, and Keystone Cliffs. It was named Mount Rushmore during a prospecting expedition by Charles Rushmore, David Swanzey (husband of Carrie Ingalls), and Bill Challis. Historian Doane Robinson conceived the idea for Mount Rushmore in 1923 to promote tourism in South Dakota. In 1924, Robinson persuaded sculptor Gutzon Borglum to travel to the Black Hills region to ensure the carving could be accomplished. Borglum had been involved in sculpting the
Gutzon Borglum of which had never been attempted before. Many difficulties slowed progress, some because of the sheer scale involved. After finishing the detailed model of the carving, Borglum was unable to trace the figures onto the massive area on which he was working, until he developed a gigantic magic lantern to project the image onto the side of the mountain. Carving officially began on June 23, 1923, with Borglum making the first cut. At Stone Mountain he developed sympathetic connections with the reorganized Ku Klux Klan, who were major financial backers for the monument. Lee's head was unveiled on Lee's birthday