Mexican Independence and Mexico’s Colonization of Texas

On September 27, 1821, the Army of the Three Guarantees entered Mexico City, marking the effective end of Spanish colonial rule after an eleven-year independence struggle.

Texas and the Road to Annexation

Texas declared independence from Mexico in 1836 and spent nearly a decade as its own republic before a bitterly contested vote in Washington — fought over slavery, sectional balance, and constitutional procedure — made it the 28th state on December 29, 1845.

The Mexican-American War Begins: A Contested Escalation

In 1846, the United States and Great Britain settled a boundary dispute that had simmered for nearly three decades—accepting a compromise at the 49th parallel rather than the 54°40′ line that expansionists had rallied around with the slogan “Fifty-Four Forty or Fight.”