Fort Smith is the third-largest city in Arkansas and one of the two county seats of Sebastian County. As of the 2010 Census, the population was 86,209. With an estimated population of 87,891 in 2019, it is the principal city of the Fort Smith, Arkansas–Oklahoma Metropolitan Statistical Area, a region of 298,592 residents that encompasses the Arkansas counties of Crawford, Franklin, and Sebastian, and the Oklahoma counties of Le Flore and Sequoyah. Fort Smith has a sister city relationship with Cisterna di Latina, Italy, site of the World War II Battle of Cisterna, fought by United States Army Rangers commanded by Fort Smith native William O. Darby. The city also has a mutual friendship-city relationship with Jining, China.Fort Smith lies on the Arkansas-Oklahoma state border, situated at the confluence of the Arkansas and Poteau rivers, also known as Belle Point. Fort Smith was established as a western frontier military post in 1817, when it was also a center of fur trading. The city developed there. It became well known as a base for migrants' settling of the "Wild West" and for its law enforcement heritage. The city government is led by Mayor George McGill (D), who made history in 2018 when he was elected as the city's first African American mayor, and a city Board of Directors composed of three members elected at-large and four members elected by ward.

Tahlequah ( TAL-ə-kwah; Cherokee: ᏓᎵᏆ, da-li-gwa) is a city in Cherokee County, Oklahoma located at the foothills of the Ozark Mountains. It is part of the Green Country region of Oklahoma and was established as a capital of the 19th-century Cherokee Nation in 1839, as part of the new settlement in Indian Territory after the Cherokee Native Americans were forced west from the American Southeast on the Trail of Tears. The city's population was 15,753 at the 2010 census, an increase of 8.96 percent over the figure of 14,458 reported in 2000. The 2019 estimated population is 16,819.Tahlequah is the capital of the two federally recognized Cherokee tribes based in Oklahoma, the modern Cherokee Nation and the United Keetoowah Band of Cherokee Indians. Tahlequah is also the county seat of Cherokee County. The main campus of Northeastern State University is located in the city.

McCurtain County is in the southeastern corner of the U.S. state of Oklahoma. As of the 2010 census, the population was 33,151. Its county seat is Idabel. It was formed at statehood from part of the earlier Choctaw Nation in Indian Territory. The name honors an influential Choctaw family that lived in the area. Green McCurtain was the last chief when Oklahoma became a state in 1907.

Muskogee () is the eleventh-largest city in Oklahoma and the county seat of Muskogee County. Home to Bacone College, it lies approximately 48 miles (77 km) southeast of Tulsa. The population of the city was 39,223 as of the 2010 census, a 2.4 percent increase from 38,310 in 2000.