Rockwall County was established in 1873 after residents of the north part of Kaufman County complained that the county seat was too far to travel in order to do business at the courthouse especially in cold and wet weather. C. L. Jones and Col. Griffith traveled to Austin in 1873 and obtained the charter for the county. The county was named for the underground formation of rock wall as was the city of Rockwall. The county was a part of Henderson County and before that Nacogdoches County before it became a part of Kaufman County. It is the smallest county in Texas.

The area that is now Rockwall County was a part of Mercer’s Colony, named for Charles Finton Mercer of Virginia. A graduate of Princeton, he became interested in Texas in 1841. He came to Peter’s Colony (Dallas area) in 1843, was given impresario rights to bring in 100 families in three years for his colony. He brought in only 108 people in a few years. He was one of first colonizers of Kaufman-Rockwall County. The area started at McKinney, encompassed Cumby, Athens, Cedar Creek, the Waco area, Peters Colony and McKinney. ‘(Information came from Pat Costello of Forney, historian.) Many people planned to travel to Peter’s Colony but when they arrived at the East Fork of the Trinity River, they could not cross due to flooding and stayed in Mercer’s Colony.

The City of Rockwall was named for the rock formation underground after the town founders could not agree on naming the town after one of them, Boystun, Bowles, and Elgin. The town was plated in 1854.

Royse City was named for G. B. Royse who platted the town site in 1886 after the MK&T Railroad had come through. Nancy McCasland, a widow, is considered the founder of the town in about 1849.

Heath was named for an early settler, E. C. Heath. It was first called Black Hills, then Willow Springs. The Heath area¬†drew the first settlers to what is now Rockwall County. The first post office for Rockwall County was located in Mr. J. O. Heath’s cabin. It was first called Trinity, Forks of Trinity, and Black Hills. J. O. was E. C.’s father who received a land grant of 620 Acres in Mercer’s in 1846.

Fate was first known as Barnes, named after Dr. W. T. Barnes who owned the land before dividing it into lots. When the MK&T railroad came through Barns in 1886, it began to grow and drew citizens from Old Fate, a short distance away. The official document for the name change from Barns to Fate occurred in February 1887.