The Pazzi Conspiracy

On this day in 1478, Pazzi conspirators attacked Florentine ruler Lorenzo de’Medici and killed his brother, Giuliano, during High Mass at the Duomo of Florence. The bloody Pazzi Conspiracy is among the boldest in Florentine history.

Rivals of the Medici, the ancient noble Tuscan family known as the Pazzi conspired to replace the Medici as rulers of Florence. Along with the Salviati, papal bankers in Florence, the Pazzi put together a plan to assassinate Lorenzo, ruler of Florence and his brother Giuliano. The plan was so widely known that Pope Sixtus IV himself was reported to have said, “I support it–as long as no one is killed.”

On Easter Sunday, 26 April 1478, during a special holiday High Mass at the splendidly decorated Duomo, a crowd of some 10,000 worshippers gathered to celebrate the traditional High Mass marking the resurrection of Jesus. Amid the thousands crowding the pews were the young Medici brothers, Lorenzo and Giuliano. Also in assembly was Francesco de’Pazzi, leader of the conspiracy. As the cardinal raised the Sacred Host high, bells rang, and the congregation bowed their heads, Francesco leapt forward, drew a dagger from his priestly garb and thrust it into the body of the unsuspecting Giuliano. Then, in front of a crowd of 10,000 worshippers, he stabbed Giuliano de’Medici 19 more times before Giuliano bled to death on the marble cathedral floor. His brother Lorenzo escaped with serious wounds and survived.

An attempt to capture the Gonfaloniere of Justice and Signoria of Florence was thwarted when the head of the Salviati clan was trapped in a room. With the conspiracy exposed and the coup failed, the Pazzi conspirators were left vulnerable to the enraged masses. Although Lorenzo appealed to the angry crowd not to exact summary justice, the enraged Florentines pursued the conspirators to death, exacting retribution on the entire Pazzi clan. They tossed Jacobo de’Pazzi, head of the house of Pazzi, from a window. From there, an angry mob mutilated him and dragged him naked through the streets, then threw him into the Arno River. Salviati was hanged on the walls of the Palazzo Vecchio. The main conspirators were hunted down in a bloodbath that saw more than 200 members of the Pazzi family and its papal allies killed. Others were beheaded. The Pazzi family was stripped of their possessions in Florence and their name erased from the city. The fortunes of Pazzi companies across Europe were ruined and the Pazzi crest was banned.

As a result of the bloodbath, the Pope Sixtus IV—a rival to the Medici—forbade Mass to be held in Florence and enlisted the King of Naples to attack the city. Before he could do so, however, Lorenzo traveled to Naples to surrender and dissuade the king from attacking. Ultimately, the Pazzi conspiracy resulted in the exact opposite of what it had intended: it weakened the Pazzi family and destroyed their chances of assuming leadership of Florence, while making the Medici stronger than ever.