Ennis is a city in Ellis County, Texas, United States. The population was 16,045 at the 2000 census. In 1871, the Houston and Texas Central Railroad (H&TC) purchased 647 acres (2.62 km) of land in Ellis County at a price of $5.00 per acre ($12.4/ha), establishing the line's northern terminus. On May 8, 1872, this site was established as the City of Ennis. The namesake of the town was Cornelius Ennis, an early official of the Houston and Texas Central Railroad. Ennis served as Mayor of Houston (1856-57), and as a director of the Houston Tap and Brazoria Railway and Houston and Texas Central Railway.