On October 31, 1835, an expedition of insurgent Texans left Goliad to capture Fort Lipantitlán, a Mexican fort across the Nueces River and three miles upstream from San Patricio. Philip Dimmitt, commander of the rebel garrison at Goliad, planned the mission, but Ira Westover was operational commander. John J. Linn, James Kerr, and James Power accompanied Westover as an unofficial advisory committee. Upon leaving Goliad the contingent numbered only thirty-five men, but recruiting in Refugio and on the line of march increased the number of participants to sixty by the time they reached the Nueces River.
The party arrived at San Patricio on the afternoon of November 3 and that night moved against the earthworks that constituted Fort Lipantitlán. Since most of the Mexican garrison, under the command of Nicolás Rodríguez, was out attempting to intercept the expedition, only a skeleton force of twenty-two troops remained to man the post. Irish-born James O'Riley, himself a captive of the Texans, entered the fort and persuaded the outnumbered garrison to yield. At 11:00 P.M. the Mexicans inside the fort surrendered; not a shot had been fired. The next morning the Texans burned the buildings around the fort and, with only limited success, dismantled the earthen breastworks. As the expedition was crossing the Nueces River to march back to Goliad, Rodríguez, leading the majority of the Lipantitlán garrison and a few Irish sympathizers, returned.
Westover's men took cover in some timber on the riverbank, and the battle of Lipantitlán (also known as the battle of Nueces Crossing) ensued. Advancing across open ground, the Mexicans fell victim to the accuracy of the Texan long rifles; some twenty-eight men were killed, wounded, or missing. William Bracken, who had three fingers shot off, was the only Texan injured. In heavy rain and a blue norther, Rodríguez withdrew to the surrounding plains. Westover, meanwhile, dumped several pieces of captured ordnance into the river and occupied San Patricio. Having no surgeon, Rodríguez requested permission to send in his wounded; Westover assented, and the injured Mexicans were treated in San Patricio. Westover sent a courier to Rodríguez requesting his attendance at "another pleasant meeting," but the Mexican captain declined, explaining that his troopers were ill-equipped to match "the Texas rifles and could not accept the invitation." Thereafter, Rodríguez retreated to Matamoros.
On the return journey to Goliad, Westover's men met Governor Agustín Viesca and escorted his entourage to Refugio. The expedition returned to Goliad on November 12 with several captured horses. Although Dimmitt was displeased with Westover's handling of the campaign, Sam Houston lauded the "conduct and bravery of the officers and men." San Patricio declared support for the Constitution of 1824, elected representatives to the Consultation, and organized a militia. Most important strategically, Mexican general Martín Perfecto de Cos and his men, besieged in San Antonio de Béxar, were denied the last link of communication between them and friendly forces inside Mexico.