Juan Cortina was born in
Camargo,
Tamaulipas Mexico, the son of Trinidad Cortina and Estéfana Goseacochea, a wealthy cattle-ranching family. At the time of his birth, his family's Espiritu Santo land grant encompassed more than 260,000 acres. When he was three, his family relocated to the
Rio Grande Valley, as his mother had inherited vast tracts of Espiritu Santo in the area surrounding Matamoros and Brownsville. In 1846, at age 22, he enlisted with a Mexican Army unit commanded by Gen.
Mariano Arista, who had arrived at Matamoros in an attempt to stop the advancing forces of Gen.
Zachary Taylor. Arista asked Cortina to form a force from the local
vaqueros (Mexican
cowboys) who worked for him and the nearby ranches. This irregular
cavalry regiment (called the
"Tamaulipas") was placed under his command, and as the
Mexican–American War began, it participated in the battles of
Palo Alto and
Resaca de la Palma. With the end of the war and the signing of the
Treaty of Guadalupe Hidalgo on February 2, 1848, the Cortina family estates were divided by the new frontier, leaving a vast portion of their lands inside
United States territory. Cortina became an important political boss for the South Texas Democratic Party, and although the new local authorities invalidated many of his land claims, he remained a large rancher. Many landowners of Mexican ancestry suffered from this situation as well, and eventually, Cortina came into conflict with an influential group of lawyers and judges of Brownsville, whom he accused of expropriating land from Mexican Texans or
"Tejanos", who were unfamiliar with the American legal system. "Flocks of vampires, in the guise of men," he wrote, robbed Mexicans "of their property, incarcerated, chased, murdered, and hunted them like wild beasts". Cortina's own skirmishes with the law steadily intensified, and he was indicted twice on charges of cattle theft. However, he was not arrested due to his already considerable popularity among the poorer
Tejanos, who considered this attempt to be nothing but another demonstration of legal harassment by the
"Anglos" (the Texans of American origin) to their class. With the self-appointed purpose of defending the rights of this
social group, Cortina gathered, trained, and armed a private army, and on many occasions, he used this force to resist the eviction of
Tejanos from their lands. As a result, he became a popular leader among the poorer local population, many of whom considered him a hero against the abuse of power by the
Anglos. In 1858, Cortina along with other rancheros attacked what was speculated to be the final surviving members of the
Karankawa Indians, a Native American people whose homeland comprised the coastline of southern Texas, "when they were surprised at their hiding place in Texas and were exterminated." ==The Cortina Troubles==