Tuscan noble who, as tyrant of Pisa and Lucca, played a role in the 14th-century Italian struggle between papal and imperial factions.

A member of an old Ghibelline (pro-imperial) family, Uguccione had served as podestà (chief magistrate) and captain general in several Italian cities when the sudden death of Holy Roman Emperor Henry VII left Ghibelline Pisa without effective leadership. Offered the position of podestà, the 60-year-old Uguccione soon became captain of war and virtual dictator. A Ghibelline rising in Lucca, led by the mercenary captain Castruccio Castracani (Castracani, Castruccio), enabled Uguccione to make an easy conquest of the neighbouring city. Invading Florentine territory in 1315, he won a resounding victory over Guelf (papal) forces at Montecatini, northwest of Florence; in 1316, however, he was overthrown in Pisa and Lucca by Castracani.

After an unsuccessful attempt to retake the two cities, aided by Cangrande I della Scala, lord of Verona, Uguccione returned to Verona and became podestà of Vicenza. He died the following year.