1368-1369. Political Revolution in Siena. The compromise government of the Riformatori is established. The Emperor Charles V. is summoned to the city by the party worsted in the Revolution, joined by certain nobles. He arrives in January, '69, but is forced to withdraw by a popular rising. The nobles are excluded from the chief power and ravaged by feuds among themselves.

1372. Gregory XI. declares war against Bernabo Visconti of Milan, and takes into his pay the English free-lance, Sir John Hawkwood. Peter d'Estaing, appointed Legate of Bologna, makes truce with Bernabo. The latter, however, continues secretly to incite Tuscany to rebel against the Pope, inflaming the indignation of the Tuscans at the arbitrary policy of the Papal Legates, and in particular of the Nuncio, Gerard du Puy, who is supporting the claims of those turbulent nobles, the Salimbeni in Siena. Catherine is in correspondence with both d'Estaing and Du Puy. On April 22nd, Gregory, in full consistory, announces his intention of returning to Rome.

1373. Italy is devastated by petty strife: "It seems as if a planet reigned at this time which produced in the world the following effects: That the Brothers of St. Austin killed their Provincial at Sant' Antonio with a knife; and in Siena was much fighting. At Assisi the Brothers Minor fought, and killed fourteen with a knife. And those of the Rose fought, and drove six away. Also, those of Certosa had great dissensions, and their General came and changed them all about. So all Religious everywhere seemed to have strife and dissension among themselves. And every Religious of whatever rule was oppressed and insulted by the world. So with brothers according to the flesh -- cousins, wives, relatives, and neighbours. It seems that there were divisions all over the whole world. In Siena, loyalty was neither proposed nor observed, gentlemen did not show it among themselves nor outside, nor did the Nine among themselves or with outside persons, nor did the Twelve. The people did not agree with their own leader, nor exactly with any one else. Thus all the world was a place of shadows." -- Chronicle of Neri di Donato.

A Crusade publicly proclaimed by the Pope.

1374. Plague and famine lay Tuscany waste. William of Noellet, the Papal Legate, refuses to allow corn to be imported into Tuscany from the Papal States. Hawkwood, probably at his instigation, ravages the country, and even threatens the city of Florence. Florence, enraged, rebels against the Pope, and appoints from the ranks of the Ghibellines a new body of Magistrates, known as the Eight of War. Meantime, Cione de' Salimbeni is raiding the country around Siena. The roads through the Maremma are insecure for peaceable folk, and the peasants are driven to take refuge in the plague-stricken town.

1375. Eighty Italian cities join a League, headed by Florence, against the Pope, with the watchword, "Fling off the foreign yoke."

1376. Gregory despatches ambassadors to the Eight of War, who scorn his proposals. Florence incites Bologna to revolt, and the Legate flees. The Papal Nuncio is flayed alive in the streets of Florence. The city is placed under an Interdict. Envoys are despatched to Avignon, who set forth eloquently, but to no avail, the grievances of the city. War is declared against Florence by the Pope, and Count Robert of Geneva, with an army of free-lances, is sent into Italy. Count Robert, laying waste the territory of Bologna, summons Hawkwood to his aid, and perpetrates the hideous massacre of Cesena. Catherine, sent to Avignon, fails to procure peace. Gregory, swayed by her representations, returns to Italy, and reaches Rome, after a difficult journey, on January 17th, 1377.

1378. Gregory, exhausted and disappointed by the continued discords in Italy, dies in March. The Archbishop of Bari, known as Urban VI., is appointed his successor. In July, peace is made with Florence, and the Interdict upon the city is raised. The harsh measures of Urban in dealing with the clergy arouse violent antagonism. In June, the Cardinals begin to circulate rumours challenging the validity of the election, and on September 20th they formally announce that the election was invalid, having been forced on them by fear, and appoint as Pope the Cardinal Robert of Geneva, who takes the name of Clement VII.

1379-1380. The Great Schism divides Europe. England remains faithful to Urban: France and Naples, after wavering, declare for Clement. War rages between the two Popes. The schismatic forces gain possession of the Castle of Saint Angelo at Rome, but are driven out by the forces of Urban, who in gratitude marches barefoot in solemn procession from Santa Maria in Trastevere, to St. Peter's. The city, however, later revolts against Urban, but is reconciled to him, partly through the efforts of Catherine. Queen Giovanna of Naples, having conspired against Urban's life, is excommunicated.