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!” 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).