After assassinating his uncle and father-in-law
Bernabò Visconti in 1385, the lord of
Pavia,
Gian Galeazzo Visconti, became ruler of
Milan, and in a short period of time established an extensive territorial state in
northern Italy, aiming to claim the title of king of
Lombardy and
Tuscany. He gained the backing of
Pope Urban IV and concluded an alliance with the
Republic of Venice, which in 1387 allowed him to conquer the cities of
Verona and
Vicenza, putting an end to the
Scaliger lordship there. Vicenza had been promised to
Padua, but Visconti kept it for himself. In 1388, with Venetian support, Visconti attacked Padua as well, forcing its lord,
Francesco Novello da Carrara, to capitulate and surrender all is domains in northern Italy—Padua itself,
Treviso,
Ceneda,
Feltre, and
Belluno—to the lord of Milan. The rapid expansion of the Viscontean state worried the
Republic of Florence. When mercenary bands formerly in the Milanese lord's employ had raided into Tuscany in 1387, the Republic suspected them to be acting on Visconti's behalf, and the latter's attack on Padua only served to confirm suspicions of his ultimate designs. Florence began a military build-up, hiring the mercenary commander
John Hawkwood, and cautiously supported the Carrara: along with
Bologna, Florence tried to mediate on their behalf with the Milanese–Venetian alliance. Soon, Florence and its environs became a haven for the anti-Visconti opposition: Bernabò Visconti's son Carlo and
Antonio I della Scala, the former lord of Verona, as well as Francesco Novello and his family. Francesco Novello joined the Florentine and Bolognese efforts to find support against Visconti among the German princes who had married Bernabò's numerous daughters, especially the
Dukes of Bavaria. Florence also made common cause with
Bologna, also a target of Visconti's ambitions. ==Prelude==