The imperialists held off and won some skirmishes, before the increasing Republican forces made them contemplate an attempt at breaking the lines and heading for the coast.

He was executed by firing squad, alongside his generals Miguel Miramón and Tomás Mejía, on the morning of 19 June at the Cerro de las Campanas.

[1] Maximilian joined the army at Querétaro along with Minister Manuel García Aguirre, Leonardo Márquez, and Miguel López with the sum of fifty thousand pesos, with sixteen hundred men and twelve cannons.

[3] A few days after his arrival a review of the troops was held, showing 9,000 men with 39 cannon, including about 600 Frenchmen, Miramón was placed at the head of the infantry, of which Castillo and Casanova received each a division, Méndez assuming command of the reserve brigade, in which Miguel López served as colonel, Mejía became chief of the cavalry, Reyes of engineers, and Arellano of the artillery.

[5] In the first council of war that had been held on 22 February, it had been agreed to fight the Republicans at once, before their combined forces became too strong, but ultimately this strategy, which historian Bancroft suggests could have achieved victory, was rejected at Márquez's behest.

[17] The Imperialists now sought to break through the enemy lines, seek refuge in the mountain range of the Sierra Gorda, and possibly reach the coast.

[18] Unfortunately for the Imperialists, before these plans were carried out they were betrayed by Colonel Miguel López who, on the night of 14 May, opened the gates of Querétaro to the Republican forces in exchange for a sum of gold.