The origin of the Texas county is found in the municipality, the unit of local government under Spanish and Mexican rule. Municipalities were rather large districts embracing one or more settlements and the surrounding rural territory. There were twenty-three of them by 1836, when Texas won her independence from Mexico. The government of the municipality was vested in an ayuntamiento (council), composed of at least one alcalde (judge), a varying number of regidors (aldermen; see REGIDOR), a síndico procurador (attorney), an alguacil (sheriff), and an escribano (secretary).
Under the Republic of Texas the municipalities became counties, but the Spanish-Mexican influence on their government was negligible. The new local governments were based on the county as found in the southern United States. The chief governing body of the county during the republic was a county board, composed of the chief justice of the county court (appointed by Congress) and elective justices of the peace, although in 1845 four elective commissioners were substituted for the justices of the peace. The other officers were the sheriff, coroner, and clerk (all elected), a tax assessor (appointed by the county board), and a surveyor (appointed by Congress). New counties could be established if 100 free male inhabitants living in an area containing at least 900 square miles petitioned the government. By 1845 Texas had thirty-six regular counties.
County government under the Constitution of 1845 varied only slightly from that under the republic, the major changes being the election of all officials and the establishment of a few new offices. By the end of 1860 the number of organized counties had increased to 122. When Texas entered the Confederacy in 1861 and adopted a new state constitution, no changes were made in county government, nor were any really significant ones made by the Constitution of 1866. The government set up by that constitution lasted only a short while because of the passage of the Reconstruction Acts in 1867. Under the military rule that followed, many local elected officials were removed indiscriminately and either were not replaced or were replaced by appointees. This constitution lasted until 1870, when the government was reorganized under the Constitution of 1869. By the end of 1870 the state had 129 organized counties. Under the Constitution of 1869 the government of the county was again in the hands of an elected county board and several other elected officers, but actual administration, up to 1873, when the radical element was overthrown, was virtually a continuation of the Reconstruction government. No real changes were made until the adoption of the Constitution of 1876.
This constitution contains much detail about the organization of county government. The chief governing agency continued to be a county board, the county commissioners' court, but provision was also made for a county judge, county attorney, county tax assessor, county surveyor, and county treasurer, as well as for the offices of constable, sheriff, justice of the peace, and clerk of the county court. In addition, there were several statutory officers, the most important of which were the county superintendent of schools and the county auditor. The constitution was also specific about the establishment of new counties: no new county from unorganized territory could be smaller than 900 square miles and should be square if possible; new counties demarked from established counties should contain not less than 700 square miles.
Early responsibilities of county governments included road construction and maintenance, law enforcement, and tax collection. As populations increased, however, county operations expanded to include such additional programs as health and social welfare, solid-waste management, and housing and community development. Environmental protection and floodplain development controls have also become concerns of county government. Texas has had 254 counties since the organization of Loving County in 1931. Voters adopted a home-rule provision in 1933, but the measure proved to be unworkable and was repealed in 1969. (see DEFUNCT COUNTIES.)