Arlington is a city in the U.S. state of Texas, located in Tarrant County. It forms part of the Mid-Cities region of the Dallas–Fort Worth–Arlington metropolitan area, and is a principal city of the metropolis and region. According to the U.S. Census Bureau's 2019 estimates, the city had a population of 398,854, making it the second-largest city in the county (after Fort Worth). Arlington is the forty-eighth-most populous city in the United States, the seventh-most populous city in the state of Texas, and the largest city in the state that is not a county seat.
Arlington is home to the University of Texas at Arlington, a major urban research university, the Arlington Assembly plant used by General Motors, the Nuclear Regulatory Commission Region IV, Texas Health Resources, Mensa International, and D. R. Horton. Additionally, Arlington hosts the Texas Rangers at Globe Life Field, the Dallas Cowboys at AT&T Stadium, the Dallas Wings at College Park Center, the International Bowling Campus (which houses the United States Bowling Congress, International Bowling Museum and the International Bowling Hall of Fame), and the theme parks Six Flags Over Texas (the original Six Flags) and Hurricane Harbor.
European settlement in the Arlington area dates back at least to the 1840s. After the May 24, 1841 battle between Texas General Edward H. Tarrant (Tarrant County is named after him) and Native Americans of the Village Creek settlement, a trading post was established at Marrow Bone Spring in present-day Arlington (historical marker at 32°42.136′N 97°6.772′W). The rich soil of the area attracted farmers, and several agriculture-related businesses were well established by the late nineteenth century.
Arlington was founded in 1876 along the Texas and Pacific Railway.