New Spain Spain, at 42d north (now the northern boundary of the U.S. states of California, Nevada, and Utah). In the 1821 Declaration of Independence of the Mexican Empire, both Mexico and Central America declared their independence after three centuries of Spanish rule and formed the First Mexican Empire, although Central America quickly rejected the union. After priest Miguel Hidalgo y Costilla's 1810 Grito de Dolores (call for independence), the insurgent army began an eleven-year war. At first, the Criollo class fought against the rebels. But in 1820, a military coup in Spain forced Ferdinand VII to accept the authority of the
First Mexican Empire First Mexican Empire The Mexican Empire (, ) was a short lived monarchy, and the first independent post-colonial imperial state in Mexico. It was the only former colony of the Spanish Empire to establish a monarchy after independence. Together with the Brazilian Empire, it was one of two European-style empires in the Americas. The Mexican Empire lasted two years. It existed from the signing of the Treaty of Córdoba and the declaration of Independence of the Mexican Empire in September 1821 until the emperor's abdication in March 1823 when the Provisional Government took power and the First Mexican Republic was