Simultaneously, Mexican president Antonio Lopez de Santa Anna led a larger force into the Texian interior, where on March 6 his troops won the Battle of the Alamo.

After learning of the Alamo's defeat, Texian general Sam Houston ordered Fannin to retreat from Goliad and join the rest of the army in Victoria.

Mexican troops surrounded the Texians later in the day before Fannin could reach the shelter of a grove of timber at Coleto Creek, some 400 yards (370 m) away.

However, Santa Anna had received authorization from the Mexican Congress to treat all captured Texian troops as pirates rather than prisoners-of-war.

Under orders from Santa Anna, and despite the appeals for clemency by General José de Urrea, the massacre was reluctantly carried out by Lt.

After the Alamo fell to Santa Anna's forces the Texians received orders from General Sam Houston to fall back to Victoria.

Nine heavy artillery pieces with different calibers were ordered by Fannin to be taken by the Texians, along with 1000 muskets, but he neglected to ensure that a good amount of food and water was transported.

The two-hour lead was removed, when a Texian cart crossing the San Antonio River broke, a cannon had to be brought out of the river, and Fannin ordered that the oxen be allowed to graze for a period of time after the Texians had proceeded about a mile past Manahuilla Creek, resulting in the retreat being stopped.

John Shackelford, Burr H. Duval, and Ira Westover opposed Fannin's decision to allow the oxen to graze, arguing that they should continue their retreat until they reached the protection of the Coleto Creek timber.

Mexican mounted scouts determined the location of the Texians, and reported the size of the force, which Urrea concluded was smaller than he originally thought.

The left of the Texian square was confronted by the rifle companies under Morales, and the right was assaulted by the grenadiers and part of the San Luis Battalion.

The Jiménez Battalion under Col. Mariano Salas fought the front, and Col. Gabriel Núñez's cavalry was ordered against the rear of the square.

Making effective use of their bayonets, multiple muskets, and nine cannons, the Texians had prevented the Mexicans each time from breaking the square.

During the day's fighting the Texian soldiers that were retreating to Guadalupe Victoria after the earlier battle of Refugio were close enough to Fannin to hear gunfire.

After one or two rounds were fired by Mexican artillery Fannin and his officers re-iterated their conclusion that the Texians could not take another day's fighting, and decided to seek honorable terms for surrender.

They drafted terms of surrender, which included statements that the Texian wounded would be treated, that they would be gain all the protection expected as prisoners of war, and that they would be paroled to the United States of America.

Urrea, meanwhile, had moved onto Guadalupe Victoria, from where he wrote to Santa Anna a letter recommending that the Texian prisoners should be treated with clemency.

However, Santa Anna did not follow Urrea's recommendation, instead ordering the Mexican commander at Goliad, Jose Nicolas de la Portilla, to execute the Texian prisoners.

[1] The battle was primarily lost because Fannin did not act decisively enough to ensure success and also underestimated the quality of the Mexican force against him.