The medal tells the story of an attack on the Medici family, plotted by their rivals in Florence, which took place in the Cathedral (Duomo) on 26 April, 1478. The Pazzi family and their allies intended the murder of Lorenzo 'Il Magnifico' ('the Magnificent') de' Medici, who through his banking wealth and political influence, had made himself effective ruler of the Florentine republic (1469-92). The plot failed, and Lorenzo was able to consolidate his power. However, his younger brother Giuliano was killed, and subsequently turned into a kind of martyr.This medal is only one of several works of art commissioned from leading artists which proclaimed the safety of the republic under Lorenzo, as well as mourning Giuliano. It was modelled by Bertoldo di Giovanni (about 1420-91), an artist then living in the Medici palace, who later taught Michelangelo. Although it was clearly intended as a piece of propaganda, the first edition of the medal was not large and in September 1478 a model for the medal was sent to Bertoldo's fellow medallist Andrea Guacialoti (1435-95) in Prato, for him to cast four specimens.