Which Japanese musical sources influenced Puccini’s score for Madama Butterfly?

To research the musical landscape for Madama Butterfly, Giacomo Puccini actively sought out authentic Japanese influences to incorporate into his score. He consulted with the wife of the Japanese ambassador to Italy, who provided him with direct exposure to Japanese culture by singing various folk songs to him and acquiring sheet music for his study.1

Puccini’s score reflects the knowledge he gained from these sources, incorporating direct references to the Japanese melodies he had been exposed to during his research. These elements were integrated into the opera to provide a sense of realism and to establish the setting, which he balanced alongside his signature melody-centered and emotionally direct operatic style.12