When during a food scarcity in 1374–75 papal legates embargoed the export of grain from the Papal States to Florence, passions reached the point of belligerence. Under the slogan Libertas inscribed in gold on a red banner, Florence organized a revolt of the Papal States in 1375 and formed a league against the papacy, joined by Milan, Bologna, Perugia, Pisa, Lucca, Genoa, and all the various potentates who had territorial ambitions in the Papal States.