The signatories were the head of the Army of the Three Guarantees, Agustín de Iturbide, and, acting on behalf of the Spanish government, Jefe Político Superior Juan O'Donojú.

In the case that none of these accept the crown, the treaty then established that Cortes could designate a new king without specifying if the person needed to belong to a European royal house.

[citation needed] The idea in this last clause had not been considered in the Plan of Iguala, and was added by Iturbide to leave open the possibility of his taking the crown.

[4] On September 27, 1821, the Army of the Three Guarantees entered triumphantly into Mexico City and on the following day, the Declaration of Independence of the Mexican Empire was widely known.

[5] The monarchy lasted three years, and after the republican revolution of Casa Mata, the Congress no longer considered the Plan of Iguala or Treaty of Córdoba in effect.