The Battle of Coleto, also known as the Battle of Coleto Creek, the Battle of the Prairie, and the Batalla del Encinal del Perdido, was fought on March 19–20, 1836, during the Goliad campaign of the Texas Revolution. In February, General José de Urrea led a branch of the Mexican army up the Gulf Coast of Mexican Texas toward Goliad, where a large contingent of soldiers from the Texian Army was garrisoned under Colonel James W. Fannin. 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.

On March 19, Fannin led his men on a leisurely retreat from Goliad. 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. Texians formed a square in the middle of the prairie and attempted to defend their position. Although Mexican troops launched three separate attacks against the square, they could not penetrate the Texian position. As night fell, Mexican sharpshooters were able to wound and kill more Texians. With little water to give to the wounded or to cool their artillery, the Texians felt they were unable to withstand further fighting. On the morning of March 20, the Texians surrendered.

Urrea attempted to secure honorable terms for his Texian prisoners. 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. Colonel José Nicolás de la Portilla.