Stefano da Bagnone (1418 - 3 May 1478) was an Italian presbyterian, known for having taken part in the Pazzi conspiracy against Lorenzo de' Medici.
Having taken his religious vows, he entered the service of Jacopo de' Pazzi, a Florentine banker, as chaplain and tutor to his daughter Caterina.
For this reason, in April 1478, he agreed to take part in the conspiracy conceived by Jacopo to kill Lorenzo and his brother Giuliano.
Initially, the two were to be eliminated during a dinner in their palace by the mercenary Giovanni Battista Montesecco, but Giuliano's absence prevented the project from being carried out.
[1][2] The conspirators then decided to eliminate the Medici brothers during the Easter mass on 26 April 1478, in the Cathedral of Santa Maria del Fiore.