Territorial evolution of Mexico

Mexico has experienced many changes in territorial organization during its history as an independent state. The territorial boundaries of Mexico were affected by presidential and imperial decrees. One such decree was the Law of Bases for the Convocation of the Constituent Congress to the Constitutive Act of the Mexican Federation, which determined the national land area as the result of integration of the jurisdictions that corresponded to New Spain, the Captaincy General of Yucatán, the Captaincy General of Guatemala and the autonomous Kingdoms of East and West. The decree resulted in the independence from Spain.

During the period of the Independence of Mexico, part of the territorial organization of New Spain was integrated into the new nation of the Mexican Empire. Added to this were the Captaincy General of Yucatán and the Captaincy General of Guatemala (whose annexation was a strategy to counteract the Spanish crown). This yielded Mexico's largest land area as an independent nation.

During the structuring of the Republic, territorial and legal changes reaffirmed the Catholic Church's status as the only religion for Mexicans. The new nation developed a popular and representative federal republic that recognized the sovereignty of the States constituting the federal union.

The liberal government of Antonio López de Santa Anna, influenced by conservatives, ratified the Seven Laws by presidential decree, establishing a new territorial court and replacing the federal states by departments whose governors and legislators would be selected by the President. This break from federalism brought Mexico its most turbulent and unstable era.

During the Second Mexican Empire, Emperor Maximilian I of Mexico made a new division of national territory.

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