On an Easter Sunday the Pazzi family plans an assassination on the Medici family. During a ceremony the Pazzi assassins attempt to take the life of Lorenzo and Giuliano, however Lorenzo is able to escape. When the Pazzi family attempts to take control of the city the citizens turn on the Pazzi. Afterwards Lorenzo takes complete control over Flornece and effectively becomes a dictator.
This is around the time that Botticelli finishes