Manuel Guerra, banker, rancher, and Democratic leader in Starr County politics, the son of Jesús Guerra Barrera, was born in Mier, Tamaulipas, in 1856. The claims of the Guerra family to land in South Texas originated in 1767, when José Alejandro Guerra secured two Spanish land grants that straddled the Rio Grande. Unlike many Hispanic families with property north of the border, the Guerras did not lose their land to aggressive Anglo ranchers and speculators. In fact, the Guerras' business enterprises and ranch holdings grew in the late nineteenth and early twentieth centuries. After living in Mier and Corpus Christi, in 1877 Manuel Guerra settled in Roma, Texas, where he launched his successful career in business and ranching and married Virginia Cox. In 1894 he won a seat on the Starr County Commissioners Court and formed an alliance with Sheriff W. W. Shely that dominated county politics until Shely became incapacitated with a nervous disorder in 1905. For the next decade Guerra ruled as the political boss of Starr County.
His reign was marked by the mobilization of lower-class Mexican-American laborers, who formed a majority of the local population, by widespread corruption and outbursts of violence, by close cooperation with the dominant political figure of the lower Rio Grande valley, James B. Wells of Cameron County, and by challenges from a growing movement of Anglo farmers and businessmen organized in the northern part of Starr County under the leadership of rancher Edward Cunningham Lasater. The political turbulence came to a climax with the election of 1906 and its aftermath. After both Guerra's Democrats and Lasater's Republicans organized large forces of armed men, the district judge, a Democrat, was murdered in his sleep the night before the election, and drunken rioting erupted in the county seat, Rio Grande City, the next day. Less than three months later, in January 1907, a Republican organizer and customs inspector, Gregorio Duffy, was killed in a gunfight involving Guerra's cousin, Deodoro, who was the newly elected sheriff. Under pressure from Republican prosecutors, a federal grand jury indicted Manuel and Deodoro Guerra, two deputies, and a Texas Ranger, for conspiring to murder a federal official, but all the defendants eventually won acquittals.
Guerra's legal victory in 1909 did not end his political problems. The collapse of a short-lived accommodation with Lasater, a state investigation confirming local charges of corruption on the part of the Guerra ring, and the development of a factional split in his party prompted the Hispanic boss to endorse a legislative scheme to organize a new county for the dissidents in the northern part of Starr County. With the formation of Brooks County in 1911, Guerra was able to complete the consolidation of his control over Starr County politics. He died on June 9, 1915, but his family continued to rule Starr County until the post-World War II era. See also BOSS RULE.