The document summarizes Texas independence and annexation by the United States. It describes how American settlers began migrating to Mexican land in the southwest US in 1821. By 1830 there were 7,000 Americans in Texas, alarming Mexico which tried to restrict further immigration. This led to American-Texan revolts and the Battle of the Alamo in 1836, after which Texas declared independence as the Republic of Texas. Texas was annexed by the United States in 1845, angering Mexico.