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 provided for another member of the
House of Bourbon to accede to the Mexican throne. However, the goal was merely a political tactic to appease the last royalists, and full independence was expected.
[4] King Ferdinand, however, refused to recognize Mexico's independence and said that Spain would not allow any other European prince to take the throne of Mexico.