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What happened during the Pazzi conspiracy against the Medici in 1478?

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Florence The Florence Cathedral, also known as the Duomo or the Cathedral of Santa Maria del Fiore, in Florence.

The Pazzi conspiracy was a failed 1478 plot to overthrow the Medici rulers of Florence. Orchestrated by the rival Pazzi family, the scheme was supported by Pope Sixtus IV, his nephew Girolamo Riario, and the archbishop of Pisa, Francesco Salviati.12

On April 26, 1478, conspirators attacked the Medici brothers during mass at the Cathedral of Florence. Giuliano de’ Medici was killed, but Lorenzo de’ Medici escaped with minor wounds by taking refuge in a sacristy. While the conspirators attempted to seize the government, the Florentine people rallied to the Medici, capturing and killing the plotters—including the archbishop, who was hanged from the Palazzo Vecchio.12

The conspiracy’s failure triggered a two-year war with the papacy, but it ultimately solidified Lorenzo’s power and public support. Following the event, Lorenzo emerged with increased prestige, eventually becoming known as "the Magnificent".12