County History
Rockwall County was created in 1873 from Kaufman County
Settlers in the area pushed for their own county in the 1870s because the Kaufman County seat was inconveniently far away — and the Texas legislature agreed.
The area that became Rockwall County was first settled by Anglo-Americans in the 1840s, when it was part of Kaufman County. The distance to the Kaufman County seat made local governance difficult. In 1873, the state legislature created Rockwall County and named Rockwall as its county seat.
The town of Rockwall was incorporated in 1874. The Texas and Pacific Railway came through in 1873, spurring growth. A courthouse fire in 1875 destroyed most early county records. The Missouri, Kansas and Texas Railroad arrived in 1886, further opening the county to agricultural trade. Cotton became the dominant crop after the railroads arrived.
Source to confirm: TSHA Handbook — Rockwall County