Embraces the counties of Big Horn, Blaine, Carbon, Cascade, Chouteau, Custer, Dawson, Fallon, Fergus, Hill, Musselshell; Park, Phillips, Prairie, Rosebud, Sheridan, Stillwater, Sweet Grass, Valley, Wibaux, and Yellowstone; area, 94,158 square miles. Erected on May 18, 1904 as a suffragan of the archdiocese of Oregon City, Oregon. Name changed to the diocese of Great Falls-Billings on February 14, 1980. Suffragan of the archdiocese of Portland, Oregon. See also