The Ritmo lucchese is an anonymous vernacular poem in a Tuscan koiné. It is reckoned one of the earliest pieces of Italian literature, composed in or shortly after 1213. It records a battle between Lucca and Pisa near Massa fought in mid-January that year. The Pisans opposed to the Visconti, along with the Massans and the Pistoiese, were led by William I of Cagliari and his father-in-law, Guido Guerra III, while the Luccans, along with a Pisan faction, were led by Ubaldo I Visconti and the deposed Pisan podestà Goffredo Musto.