They chose High Mass to commit murder. They chose wrong.

Blood in the Cathedral: The Pazzi Conspiracy

When rival bankers tried to murder Florence's ruling family in church

The Pazzi family's attempt to murder the Medici brothers during Easter Mass failed, leaving one dead but Lorenzo the Magnificent alive — and more powerful than ever.

The conspiracy was planned with extraordinary audacity: assassinate both Lorenzo and Giuliano de' Medici simultaneously, during High Mass at Florence's Cathedral of Santa Maria del Fiore, on the holiest Sunday of the Christian calendar. Easter Sunday, April 26, 1478.

The Pazzi family — rival Florentine bankers backed by Pope Sixtus IV and the Archbishop of Pisa — had grown furious with Medici dominance. The Pope himself, eager to break Medici power in Italy, had blessed the plot. Even the signal to begin the attack was consecrated: the conspirators would strike at the moment the priest elevated the host.

When the moment came, Francesco de' Pazzi stabbed Giuliano de' Medici nineteen times with such frenzy that he accidentally wounded himself in the thigh. Lorenzo, however, was wounded only slightly. Wrapping his cloak around his arm as a shield, he escaped into the sacristy with his friends, locking the massive bronze doors against the assassins.

The aftermath was brutal. Lorenzo, recovering, ordered the conspirators hunted down. Francesco de' Pazzi was hanged from a palace window still wearing his shirt. The Archbishop of Pisa was executed while in full church vestments. The Paz…

💡 Leonardo da Vinci, who was in Florence at the time, sketched several of the executed conspirators hanging from Florentine windows. The drawings survive.