First Mexican Empire of independence and a constitution with the preservation of Catholic monarchy, brought together all Mexican factions. Under the 24 February 1821 Plan of Iguala, to which most of the provinces subscribed, the Mexican Congress established a regency council which was headed by Iturbide. After signing the Declaration of Independence of the Mexican Empire of 28 September 1821, the Mexican Congress intended to establish a commonwealth whereby the King of Spain, Ferdinand VII, would also be emperor of Mexico, and both countries would be governed by separate laws and form separate legislative bodies. If the king refused the position, the law
Mexican–American War could not be released from its obligations. The US was released from all obligations of Article XI five years later by Article II of the Gadsden Purchase of 1853. The 1848 Treaty of Guadalupe Hidalgo ended the war and enforced the Mexican Cession of the northern territories of Alta California and Santa Fe de Nuevo México to the United States. Mexico acknowledged the loss of what became the State of Texas and accepted the Rio Grande as its northern border with the U.S. The losses amounted to one-third of its original territory from its 1821 independence. Before the secession of