It was also the only former viceroyalty of the Spanish Empire to establish a monarchy after gaining independence. The empire existed from to , making it one of the few modern-era independent monarchies in the Americas.
To distinguish it from the later Second Mexican Empire β under Emperor Maximilian , this historical period is commonly referred to as the First Mexican Empire. The establishment of a monarchy was the initial goal for an independent Mexico, [ 3 ] as outlined in the Plan of Iguala , a political document drafted by Iturbide that unified the forces fighting for independence from Spain. Iturbide's popularity reached its peak on May 18, , when public demonstrations called for him to become emperor in the absence of a European royal willing to assume the throne.
The Mexican Congress approved the proposal, and Iturbide was crowned in July The empire's brief existence was marked by challenges, including disputes over its legitimacy, conflicts between the Congress and the emperor, and a bankrupt national treasury.
In October , Iturbide dissolved Congress and replaced it with the National Institutional Junta , composed of his supporters. However, by December of the same year, he began to lose the support of the Mexican Army , which rebelled in favor of restoring the Congress and its democratic powers. Unable to suppress the revolt, Iturbide reconvened the Congress in March and offered his abdication.
Power was then transferred to a republican provisional government of , which abolished the monarchy and established the First Mexican Republic. The Spanish Empire disintegrated in the wake of Napoleon 's invasion of Spain and the overthrow of the Spanish Bourbons in Throughout Spain and its viceroyalties there was a widespread refusal to recognize Napoleon's brother Joseph I as the new French-backed king of Spain.
