The theme of the murals is the conquest of Mexico by the Spaniards.
The villian of the story is the Spanish conquistador, Cortez. Although Mexico is an Hispanic country, the Mexicans take greater pride in their Indian heritage than in their Spanish background. You will find no monuments to Cortez in Mexico...he is the "bad guy" who destroyed the native civilizations and enslaved the Indian population.
The Spanish soldiers are portrayed as inhuman, robot-like machines of destruction.
In the dome is Orozco's masterpiece, "Man In Flames," which conveys the artist's hope that mankind through its suffering will eventually find the path to heaven