When his family was exiled from Perugia and he lost the castle of Montone, he entered Alberico da Barbiano’s "Company of St. George", in which he would make friends with Muzio Attendolo Sforza.

He ravaged the lands of the Trinci of Foligno but, when Perugia accepted Ladislaus' suzerainty, Braccio sided against him and moved to Ancona, capturing Jesi.

In 1409 Braccio fought at Città di Castello, for the Florentines and then moved to Rome where he besieged Castel Sant'Angelo, returning to the Marche for the winter.

In 1414 he fought in Todi against Sforza, who had been hired by the King of Naples; in June he entered Florence, with which he signed a pact of alliance for 10 years.

At the battle of Sant'Egidio (12 July 1416, later portrayed in a famous fresco by Paolo Uccello), the bracceschi were victorious, and Perugia was finally forced to open its gates to Braccio da Montone.

Other Umbrian cities, such as Todi, Narni, Orvieto and Terni named him as lord: at this point, Braccio da Montone was ready to form a state for himself in central Italy.

On 14 March 1419, he met the Pope in Florence, obtaining the long-awaited title (including the lordships of Perugia, Todi, Assisi, Spello, Jesi and others) in exchange for ousting Antongaleazzo Bentivoglio from Bologna.

Sometime later the Pope excommunicated Joanna II, Queen of Naples, appointing Louis III of Anjou as heir to the crown in her stead.

The Pope had him buried in unconsecrated ground because Braccio died excommunicated, in which his corpse remained until 1432 when his nephew Niccolò Fortebraccio[b] moved it to the church of San Francesco al Prato in Perugia.