Poplar is located in Roosevelt County 22 miles east of Wolf Point between Brockton and Frazer on US 2 near the Missouri River. It lies on the Fort Peck Indian Reservation, home to the Assiniboine and Sioux tribes. The Poplar Museum and Tribal Museum feature tribal history and artifacts. There are many tribal celebrations throughout the year, including the "Poplar Indian Days" held annually the first weekend in September or Labor Day weekend