On April 21, 1836, during Texas’ war for independence from Mexico, the Texas militia under Sam Houston (1793-1863) launched a surprise attack against the forces of Mexican General Antonio Lopez de Santa Anna (1794-1876) at the Battle of San Jacinto, near present-day Houston, Texas. The Mexicans were thoroughly routed, and hundreds were taken prisoner, including Santa Anna. In exchange for his freedom, Santa Anna signed a treaty recognizing Texas’ independence.
Battle of San Jacinto: Background
After gaining independence from Spain in the 1820s, Mexico welcomed foreign settlers to sparsely populated Texas, and a large group of Americans led by Stephen F. Austin (1793-1836) settled along the Brazos River. The Americans soon outnumbered the resident Mexicans, and by the 1830s attempts by the Mexican government to regulate these semi-autonomous American communities led to rebellion. In March 1836, in the midst of armed conflict with the Mexican government, Texas declared its independence from Mexico.
The Texas volunteer soldiers initially suffered defeat against the forces of General Antonio Lopez de Santa Anna–Sam Houston’s troops were forced into an eastward retreat, and the Alamo (a fort near present-day San Antonio that was occupied by a small but determined group of Texas forces starting in December 1835) fell in March 1836.
Battle of San Jacinto: April 1836
From March to May, Mexican forces once again occupied the Alamo. For the Texans, the Battle of the Alamo became a symbol of heroic resistance and a rallying cry in their struggle for independence. On April 21, 1836, Sam Houston and some 800 Texans defeated Santa Anna’s Mexican force of approximately 1,500 men at the Battle of San Jacinto, shouting “Remember the Alamo!” and "Remember Goliad!" as they attacked. The victory ensured the success of Texan independence: In mid-May, Santa Anna, who had been taken prisoner during the battle, signed a peace treaty at Velasco, Texas, in which he recognized Texas’ independence in exchange for his freedom. However, the treaty was later abrogated and tensions built up along the Texas-Mexico border.
The citizens of the so-called Lone Star Republic elected Sam Houston as president and endorsed the entrance of Texas into the United States. However, the likelihood of Texas joining the Union as a slave state delayed any formal action by the U.S. Congress for more than a decade. Finally, in 1845, President John Tyler (1790-1862) orchestrated a compromise in which Texas would join the United States as a slave state. On December 29, 1845, Texas entered the United States as the 28th state, broadening the differences in America over the issue of slavery and igniting the Mexican-American War (1846-48).