Many factors caused the United States to declare war upon Mexico.  For example, the two nations spoke different languages and had different religions. The United States was full of energy and trying to expand.  Mexico had little unity, was sparsely populated, and weakened due to an oppressive upper class.  The American mind was thinking about Manifest Destiny, and Mexico had control over Texas, California, and New Mexico. The Mexican government wanted settlers from America to colonize Texas.  The only rules were no slaves and that the settlers had to become Catholic. But few Americans who settled there heeded these rules.  To make matters worse, on December 16, 1826, a few armed Americans went to Nacodoches (an area of Texas) and claimed it, calling it the Republic of Fredonia.  They won a small battle with the help of some local Indians.  When a larger force of Mexican soldiers came to put down the rebellion, they found out that the "Fredonians" had escaped to Louisiana.

           Mexico responded to this violence with the Decree of April 6, 1830.  This prohibited more Americans from immigrating to Texas and set new taxes on commerce.  Also, General Antonio López de Santa Anna became the Dictator of Mexico in 1834.  The Texans resisted his authority.  Stephen Austin, a well-known Texan, was jailed when the Mexican government obtained a letter he had written advising Texans to form their own state.  War broke out between the Texans and Mexico soon after.
            The Texans claiming to be fighting for the restoration of democracy in Mexico, captured the cities of Gonzales, Goliad, and San Antonio.  After these initial successes most Texans went home for the winter, leaving only 155 men to protect San Antonio.  They were not expecting the Mexicans to return anytime soon.  But, on February 23, 1836, General Santa Anna arrived with large force of soldiers and entered San Antonio.  The defenders retreated to the Alamo, a former mission near San Antonio.  Their leader, Colonel William B. Travis, tried to get reinforcements, but only 32 men from Gonzales were able to come.  The Mexican army numbered 2000 men, while there were a mere 187 soldiers and 15 civilians inside the Alamo's walls.  Santa Anna's forces surrounded the small mission and repeatedly attacked, but was repelled each time by the Texans.  Santa Anna lost many men with each attack, but he pressed the assault.  During one such attack, Travis declared, "I shall never surrender or retreat!  I am determined to sustain myself as long as possible and die like a soldier who never forgets what is due to his own honor and that of his country - Victory or Death!"

           From February 23 to March 5, the heroic men defended the Alamo.  But, early in the morning on March 6, Santa Anna ordered all remaining troops to attack.  Twice they were repelled, but on the third charge, they breached the Alamo's walls.  A hand-to-hand fight ensued.  Any weapon one could find was used, including knives and rifle butts.  One Texan was shot while trying to light the powder store to blow up the Alamo and everyone inside.  The Texans fought wildly, but in the end, all 187 of the Alamo's defenders were killed.  Only the civilians survived.

            Among the dead were Travis (who fought even though he had typhoid and pneumonia), frontier hero and politician Davy Crockett, and pioneer and knife maker James Bowie, all of whom were respected Colonels in the Texan army.

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