After capturing Puebla in May, 1863, a French army numbering some thirty thousand men entered the capital and installed an assemblage of notables belonging to the clerical and conservative groups.

This body thereupon proclaimed the establishment of a constitutional monarchy under an emperor.

The title was to be offered to Maximilian, Archduke of Austria.
In case he should not accept, the matter was to be referred to the "benevolence of his majesty, the Emperor of the French," who might then select some other Catholic prince.
On his arrival, a year later, the amiable and well-meaning Maximilian soon discovered that, instead of being an "Emperor," he was actually little more than a precarious chief of a faction sustained by the bayonets of a foreign army.

In the northern part of Mexico, Juarez, Porfirio Diaz,--later to become the most renowned of presidential autocrats,--and other patriot leaders, though hunted from place to place, held firmly to their resolve never to bow to the yoke of the pretender.

Nor could Maximilian be sure of the loyalty of even his supposed adherents.