Reuters photographer Stephanie Keith was recently invited by Lakota medicine man Ivan Lookinghorse to cover a 400-mile horse ride from Green Grass, South Dakota, to Fort Laramie, Wyoming, commemorating 150 years of the Fort Laramie peace treaty between the Sioux Nation and U.S. government. Keith said: “Under the treaty, the federal government recognized the Black Hills of the Dakota Territory as part of the Great Sioux Reservation and hostilities ended between the Sioux and white settlers.” Keith accompanied the Fort Laramie treaty riders all the way to Fort Laramie, where the treaty was originally signed, and also spent time with other tribe members and the extended Lookinghorse family in South Dakota.