Clarksville, Texas is the county seat of Red River County, and is located 58 miles northwest of Texarkana. The townsite was established in 1833, by James Clark. In 1837, town was incorporated by an act of the Texas Congress, and became an educational and agricultural center. In 1846, a post office was established. From the late 1830s, until the Civil War, Clarksville was the most important trading post in Northwest Texas. In 1840, the first courthouse was erected, which was replaced in 1850, by a larger brick structure at the center of a large public square. By 1914, Clarksville’s population had climbed to 3,000, but Great Depression hit the community hard and sent it into recession until the mid 1930s, when oil was also discovered at Talco, just 16 miles south. After WWII, Clarksville began to feel the effects of the declining agricultural business, and then the oil industry declined.