When the U.S. Congress passed the Homestead Act in 1862, this brought a flood of emigrants into the Badlands of South Dakota, where they could purchase 160 acres for a token payment of about $18. As the push for western expansion continued, the Sioux retaliated more and more against the many settlers encroaching upon their lands, ultimately culminating with the Fort Laramie Treaty of 1868. Photo by Carol Highsmith, 2009.