Miller County, Arkansas

Miller County is a county located in the southwestern corner of the U.S. state of Arkansas. As of the 2020 census, the population was 42,600. The county seat is Texarkana. Miller County is part of the Texarkana, TX-AR, Metropolitan Statistical Area.

When first formed, Miller County was Arkansas's sixth county, established on April 1, 1820, and named for James Miller, the first governor of the Arkansas Territory. Additionally, Miller County was the first of the state's counties to be formed upon the creation of the Arkansas Territory. The first five — Arkansas, Lawrence, Clark, Hempstead and Pulaski — were formed during Arkansas's days as part of the Missouri Territory. This county was abolished in 1838.

During the Reconstruction era, it was organized again on December 22, 1874, from a portion of neighboring Lafayette County.

When created in 1820, Miller County included most of the current Miller County, as well as several present-day Texas counties. In 1831 the county seat was located what is the current day Clarksville, Texas.

When Arkansas achieved statehood the same year as Texas declared itself an independent republic in 1836, a dispute arose over their common border, with the area in Miller County having representation in both the Arkansas legislature and the Texas congress. In 1837 and 1838, Texas organized Red River and Fannin counties, respectively, in the area. Arkansas attempted to counter by making it a misdemeanor for Miller County residents to hold office in Texas, and then by establishing a county court in Fannin. The attempts were ultimately unsuccessful. In 1845 Texas agreed to annexation by the United States, settling the boundary between Texas and Arkansas. As much of Miller County was lost to Texas, the county was dissolved, with the remaining territory returning to Lafayette County.

The modern Miller County was re-created in 1874 from the parts of Lafayette County lying west and south of the Red River.

Miller County is located in the southwest corner of Arkansas in the Piney Woods, a temperate coniferous forest. The forests of pine trees initially formed a logging and silviculture industry, though many fields have been cleared from the forest to grow rice, soybeans, corn, and vegetables. The county is also within the Ark-La-Tex region, sharing a tripoint with Texas and Louisiana. The Ark-La-Tex is an economic region anchored by Shreveport, Louisiana, Tyler, Texas, Longview, Texas, and Texarkana. The Red River serves as the northern and eastern boundary of the county, though the watercourse has shifted since the county's reestablishment in 1874. The original Red River continues to serve as the county line between Little River, Hempstead, and Lafayette counties in Arkansas. According to the U.S. Census Bureau, Miller County has a total area of 637.48 square miles (1,651.1 km²), of which 623.98 square miles (1,616.1 km²) is land and 13.50 square miles (35.0 km²) (2.1%) is water.

The county is located approximately 143 miles (230 km) southwest of Little Rock, 73 miles (117 km) north of Shreveport, Louisiana, and 204 miles (328 km) east of the Dallas–Fort Worth metroplex (DFW) in Texas. Miller County is surrounded by three Arkansas counties: Little River County to the north, Hempstead County to the northeast, Lafayette County to the east; two Louisiana parishes: Bossier Parish to the southeast and Caddo Parish, to the south; and two Texas counties to the west: Cass and Bowie.