In the age of Alfonso II D'Este (1533-1597), the "tournois a theme" developed into a more complex performance, the "cavalleria," which involved stage-setting, acting, music, dancing, machinery and firework displays. One of its most accomplished examples was the "cavalleria" "L'Isola Beata" (1569), which is fully described and analysed in this work. The "cavalleria" also influenced the development of dramatic tournaments in the Italian courts, and anticipated a new form of performance in the Baroque period, the "opera-torneo.""