Alexander Gardner took some of our most important photographs of the Civil War and the 19th-century West. His images from the crucial 1868 treaty negotiations at Fort Laramie capture Sioux, Crow, Northern Cheyenne and Arapaho people, mixed-race families and interpreters, government peace commissioners and vivid scenes of life at the fort.

Shortly after Congress gave him the power to do so, President Theodore Roosevelt in 1906 created the nation’s first national monument at Devils Tower. Wyoming’s lone congressman, Frank Mondell, fearing federal overreach and always in favor of developing, not protecting, public land was distinctly unenthusiastic about the move.