As part of the Goliad Campaign to retake the Texas Gulf Coast, Mexican troops ambushed a group of Texians on March 2, 1836.

The skirmish began approximately 26 miles (42 km) south of San Patricio, in territory belonging to the Mexican state of Tamaulipas.

Unknown to the Texians, on February 18, Mexican General José de Urrea led a large contingent of troops from Matamoros into Texas to neutralize the rebels gathered along the coast.

Several days later, informants revealed Grant's location, and on the morning of March 2, Urrea sent 150 troops to ambush the rebels.

The Texian immigrants refused to comply with Mexico's new bans on slavery, and described Santa Anna's attempts to free their slaves as "piratical attacks" to take their "property".

[8] Members of the General Council, the interim Texas governing body, were enamored with the idea of a Matamoros Expedition.

[11] Determined to quash the rebellion, Santa Anna began assembling a large force to restore order.

Others joined the troops stationed under Houston's second-in-command, James Fannin, at Presidio La Bahía in Goliad.

[21] Despite hearing rumors that the Mexican Army was approaching, Grant and Johnson chose to take their men south of the Nueces River, into territory belonging to the state of Tamaulipas, to search for horses to buy, steal, or otherwise gather.

[23][24] While Urrea waited for reinforcements before beginning his march towards Goliad, his advance party searched for Grant and the remaining Texians.

[25] Unaware of Johnson's fate, on February 27 Grant and his party began their march northward to San Patricio, driving a herd of several hundred horses he had purchased.

[27] Grant's company comprised about 53 men, including a large contingent of Tejanos (Mexican-born residents of Texas) under the command of Plácido Benavides.

[30] Grant, Benavides, and Ruben Brown rode 0.5 miles (0.80 km) ahead of the main body of Texians and saw no signs of Mexican soldiers.

[30] Five Texians dismounted and made a run for a small village nearby, hoping to gain cover so they could use their rifles.

[34] The three Texians ran for 6–7 miles (9.7–11.3 km), occasionally firing their pistols to force Mexican dragoons to stay back.

[35] Benavides had the strongest mount, and Grant ordered him to go ahead to warn Fannin that the Mexican Army was close to Goliad.

[1][36] Historian Stuart Reid theorizes that Mexican soldiers were eager to ensure Grant did not survive the battle.

Grant could identify federalist sympathizers in Matamoros and the surrounding areas, and his knowledge potentially put Urrea and some of his federalist-sympathizing troops at risk.

[36] Brown threw his empty pistol at one Mexican officer, then grabbed the lance from the man Grant had shot and used it to defend himself.

[45] Fannin wrote to the Acting Governor, James Robinson, "I am a better judge of my military abilities than others, and if I am qualified to command an Army, I have not found it out.

"[47] The acting Texas government nonetheless left Fannin in charge of the fort at Goliad, instructing him to determine whether it was best to retreat or make a stand.

The Texians surrendered after the Battle of Coleto and most, including Colonel Fannin, were executed a week later in the Goliad massacre.