Fort Smith is the second-largest city in the U.S. state of Arkansas and one of the two county seats of Sebastian County. With an population of 86,209 in 2010, it is the principal city of the Fort Smith, Arkansas-Oklahoma Metropolitan Statistical Area, a region of 298,592 residents which encompasses the Arkansas counties of Crawford, Franklin, and Sebastian, and the Oklahoma counties Le Flore and Sequoyah.Fort Smith has a sister city relationship with Cisterna, Italy, site of the World War II Battle of Cisterna fought by the United States Army Rangers commanded by Fort Smith native William O. Darby.Fort Smith lies on the Arkansas-Oklahoma state border, situated at the junction of the Arkansas and Poteau Rivers, also known as Belle Point. The city began as a western frontier military post in 1817 and would later become well-known for its role in the settling of the "Wild West" and its law enforcement heritage.In 2007, Fort Smith was selected by the US Department of the Interior to be the location of the new US Marshal Service National Museum.Fort Smith has seen a national surge in popularity due to the recent success of the Oscar nominated film True Grit, a 2010 Western film directed by Joel and Ethan Coen and starring Jeff Bridges, which is set in and around historic Fort Smith in the 1870s.