March 1836 saw Texans’ fight for their independence in peril. Early victories had been earned by Texans at Gonzales (Come and Take It), Concepcion and a battle west of San Antonio over a supply line (the Grass Fight). On March 2, 1836 Texas independence from Mexico was declared. Just a about a week before on February 23, a large, strong Mexican army of possibly 7,000 troops lead by General Antonio Lopez de Santa Anna arrived in San Antonio to crush the rebellion. On March 6, the Alamo fell as did 150 -190 of those defending it. More defeats were being dealt to Texans by Mexican General José de Urrea troops on a campaign up the Texas coast, defeating all in its path and executing most. Santa Anna’s army headed east in pursuit of the Texian army lead by Sam Houston. Houston commanded an organized and defended withdrawl accompanied by fleeing civilians. The Texas army crossed the Brazos River heading east and south. By the end of March, they were near Galveston with the Mexican army in pursuit.
For more details and history, see the San Jacinto Museum of History’s Texas independence time.