The Land Run of 1892 was the opening of the Cheyenne-Arapaho Reservation to settlement in the U.S. state of Oklahoma. One of seven in Oklahoma, it occurred on April 19, 1892, and opened up land that would become Blaine, Custer, Dewey, Washita, and Roger Mills counties.[1][2] The land run also opened up what would become part of Ellis County, but was designated County "E" and then Day County prior to statehood.[2]