War of the Eight Saints

The causes of the war were rooted in interrelated issues, Florentine opposition to the expansion of the Papal States in central Italy (which the Avignon Popes had set as a condition for their return), and antipathy toward the Parte Guelfa in Florence.

[2] When Gregory XI's war against Milan ended in 1375, many Florentines feared that the pope would turn his military attention toward Tuscany; thus, Florence arranged a nonaggression pact with the English condottiere John Hawkwood, who was Gregory XI's main military commander, at a cost of 130,000 florins, extracted from local clergy, bishops, abbots, monasteries and ecclesiastical institutions, by an eight-member committee appointed by the Signoria of Florence, the Otto dei Preti.

[4] The transalpine mercenaries employed by Gregory XI against Milan, now unemployed, were often a source of friction and conflict in papal towns.

[3] The edifice of the Florentine inquisition was destroyed, and the Signoria rolled back legal restrictions on usury and other practices frowned on by the (now defunct) ecclesiastical courts.

[3] The heavy fines and confiscations issued by the Signoria on prelates who left their posts,[3] the "most extensive liquidation of an ecclesiastical patrimony attempted anywhere in Europe before the Reformation," may have been motivated to pay for the increasingly expensive conflict.

[3] In 1377, Cardinal Robert of Geneva (future Avignon Pope Clement VII) led the army of Gregory XI in an attempt to quell the revolt, and Gregory XI himself returned to Italy to secure his Roman possessions, de facto ending the Avignon Papacy.

In contrast, the moniker is used in the March 31, 1376 bull of excommunication to refer to the Otto dei Preti (the levy committee, literally meaning "Eight of Priests").

The Otto della Guerra (war council) were appointed August 14, 1376 and consisted of four guild representatives and four members of the nobility.