Hallettsville, the county seat of Lavaca County, is on the Lavaca River at the intersection of U.S. Highway 77 and alternate U.S. Highway 90A, eighty miles southeast of Austin. One of the first settlers in the area was John Hallett, who received a land grant from Stephen F. Austin in 1831. After Hallett's death in 1836 his wife, Margaret L. Hallett, donated land for the townsite. Other early settlers were Collatinus Ballard, David Ives, Dr. M. B. Bennett, Ira McDaniel, and A. W. Hicks. A post office was opened in 1849. Hallettsville was chosen county seat when La Baca County was formed in 1842, but the county was afterward abolished. After Texas became a state and Lavaca County was organized in 1846, Hallettsville and the nearby town of Petersburg competed to be county seat. In an election held on June 14, 1852, Hallettsville received a majority of votes, but residents of Petersburg contested the results. Though Hallettsville was officially declared the county seat on August 28, 1852, allegations of election fraud and legal maneuvering were not completely resolved by the courts until 1860. The courthouse, which was completed in 1853, proved inadequate and was replaced in 1875. The present courthouse, built in 1897, is listed in the National Register of Historic Places. Hallettsville voted to incorporate on August 13, 1870. It surrendered its charter in 1875 but reincorporated on June 29, 1888. The population rose from an estimated 600 in 1875 to 1,700 in 1890. Many who settled in Hallettsville in the late nineteenth century immigrated from Czechoslovakia and Germany. The Alma Male and Female Institute, one of the county's first private schools, opened in Hallettsville in 1852 but was forced to close at the outbreak of the Civil War. Sacred Heart Academy was founded in 1881, and a public school system was in place by the late 1880s. In 1887 the San Antonio and Aransas Pass Railway built through the town, and Hallettsville became the principal trading center and shipping point for area farmers and ranchers. By 1892 the town owned an electricity plant and had established a waterworks supplied by artesian wells.
The Hallettsville Lone Star, begun by S. A. Benton in 1860, was the first newspaper in Lavaca County, but it folded when the Civil War began. The Herald was established in 1871. Publication of weekly newspapers in Czech and German began in the 1890s. By 1913 Halletsville, with an estimated population of 1,300 residents, had thirteen newspapers with a combined circulation of 25,000. One of these, the Rebel, was the state paper of the Socialist party from 1911 to 1917. In the late 1980s the only major newspaper was the Tribune-Herald. Much of the economy is based on agriculture. Area farmers raise cattle and grow rice, corn, hay, fruit, and pecans. The town is also the site of the Lavaca Medical Center, a portable-building plant, and a major soda-bottling plant. In 1988 Hallettsville had a population of 2,589. In 1990 the population was 2,718, and in 2000 it was 2,345.