The Mexican Frontier, 1821–1846 The Mexican Frontier, 1821–1846 The Mexican Frontier, 1821–1846: The American Southwest Under Mexico by historian David J. Weber is a history of the part of Mexico's north and northwest that became part of the United States after the Mexican–American War. The book examines territories on the northern frontier of Mexico, including what is now Arizona, California, New Mexico, and Texas, in the twenty-five years after Mexico gained its independence from Spain. Weber emphasizes the role of Mexicans in the region through this period of transition, particularly before and during the Texas war of independence, as well as exploring the region
Mexican War of Independence of Iguala, Iturbide persuaded Guerrero to join his forces in support of this conservative independence movement. A new army, the Army of the Three Guarantees, was placed under Iturbide's command to enforce the Plan of Iguala. The plan was so broadly based that it pleased both patriots and loyalists. The goal of independence and the protection of Roman Catholicism brought together all factions. Iturbide's army was joined by rebel forces from all over Mexico. When the rebels' victory became certain, the Viceroy resigned. On August 24, 1821, representatives of the Spanish crown and Iturbide signed the Treaty of Córdoba, which