Caldwell, the county seat of Burleson County, is at the intersection of State highways 21 and 36, in the center of the county. In 1840, when the Texas Congress annexed to Milam County all of Washington County north of Yegua Creek and west of the Brazos River, Caldwell was designated as the county seat of a new county to be formed. The masonic building in Caldwell The proposed town, surveyed by George B. Erath and named for Mathew Caldwell, was laid out parallel to the Old San Antonio Road and west of Davidson Creek; the site encompassed a settlement founded by Lewis L. Chiles. Until Burleson County was organized in 1846, Caldwell served as the county seat of Milam County.