A native of Virginia, Ellis was a well-known attorney , and before moving to Texas, lived for a time in Alabama, serving as a court judge until 1825. He had been a resident of  [what would become the State of] Texas only two years when he was selected to preside over the signing of the Texas Declaration of Independence. During the days of the Republic, he served as a Senator representting northeastern Texas. In 1936, the Texas Centennial year, a statue of Ellis was erected on the courthouse lawn in Waxahachie.

The early Ellis County courts met at the home of Emory W. Rogers. See Early Court Minutes. At an election in August 1850,  several sites had been considered, but Waxahachie was chosen as the county seat. The name is an Indian word meaning "Buffalo Creek" or "Cow Creek."

Joseph N. Whittenburg was paid $59.00 for building the first courthouse. David P. Fearis was commissioned to built a second structure which was completed in 1854. Nearly twenty years went by before a third building was erected in the 1870s . It was used for several years, but by  the mid-1890s, a larger building was needed. The present courthouse was ready for occupancy in the late 1900s. It is an elaborate structure consisting of red granite [as was used on the State Capitol in Austin] complete with a clock tower. Ellis County is one of about 40 Texas counties having such a feature. See Courthouse Restoration.

Ellis County was one of the leading agricultural counties in the state, but after the Civil War, cotton became the principal crop, and from the 1880s to the 1920s, the county was recognized as one of the top cotton producers in the world.   Every community had a gin - sometimes two or three in the larger towns. Waxahachie could boast of its own cotton mill where the raw product was turned into fiber.

The first school in the county was organized at Milford in 1855. In 1860 the Waxahachie Academy was founded but after the Masonic Lodge bought most of the stock, it was better known as the Masonic Academy. Marvin College flourished from 1866 until 1889 and Trinity University was located at Waxahachie from 1902 until 1942. Ovilla became the first city incorporated in 1844.