When Domingo de Ugartechea , military commander in Texas, received word that the American colonists of Gonzales refused to surrender a small cannon that had been given that settlement in 1831 as a defense against the Indians, he dispatched Francisco de Castañeda and 100 dragoons to retrieve it. Ugartechea realized that, given the tensions between the Texans and Antonio López de Santa Anna 's Centralist government, the slightest provocation might ignite hostilities. He therefore instructed Castañeda to use force if necessary but to avoid open conflict if possible. The company rode out of San Antonio de Béxar on September 27, 1835.
When Castañeda's troops reached the Guadalupe River opposite Gonzales on September 29 they found their path blocked by high water and eighteen militiamen (later called the Old Eighteen). Castañeda announced that he carried a dispatch for alcalde Andrew Ponton but was informed that he was out of town and that the Mexican dragoons would have to wait on the west side of the river until he returned. Unable to proceed, Castañeda pitched camp 300 yards from the ford.
As he awaited word from the absent alcalde, the men of Gonzales summoned reinforcements from several of the surrounding settlements. Later, a Coushatta Indian entered the Mexican camp and informed Castañeda that the number of Texan volunteers now numbered at least 140 and more were expected. Knowing he could not force the guarded crossing, Castañeda abandoned his campsite near the ford and marched his troops in search of another place not so well defended, where he could "cross without any embarrassment." Around sundown on October 1 he ordered his dragoons to pitch camp seven miles upriver from the contested ford on land belonging to colonist Ezekiel Williams.
The Texans were also on the move. On the night of October 1 their troops crossed to the west bank of the Guadalupe and marched upriver toward Castañeda's new camp. On the morning of October 2 they attacked the Mexicans, and Castañeda ordered his men to fall back to a low rise behind their camp.
During a lull in the fighting Castañeda arranged a parley with Texan commander John Henry Moore. Castañeda inquired why he and his men had been attacked without provocation, and Moore replied that the Texans were fighting to keep their cannon and to uphold the Constitution of 1824. Castañeda then assured Moore that he was himself a Federalist and personally opposed to the policies of Santa Anna. He added that he had no wish to fight colonists; he only had orders to reclaim the cannon. Moore then invited Castañeda to join the Texans in their fight for the federal Constitution of 1824. Castañeda explained that as a soldier he was obliged to follow his orders, whether or not he agreed with the politics behind them. At that point negotiations broke down, and the two commanders returned to their respective units.
When the fighting resumed, Castañeda, finding himself outnumbered and outgunned, ordered a withdrawal toward Bexar. He may also have been mindful of his orders not to participate in actions that were likely to bring about a conflict. In his report to Ugartechea, Castañeda stated that "since the orders from your Lordship were for me to withdraw without compromising the honor of Mexican arms, I did so." Despite Castañeda's efforts to avoid war, the so-called battle of Gonzales (which was really only a brief skirmish) marked a clear break between the American colonists and the Mexican government.