Italian operas can provide relevant information on the medical knowledge during the Romantic Age, especially in the field of neuroscience. One of the most renowned operas, “Nabucco” by Giuseppe Verdi (1813-1901) may provide us with some information on the state of knowledge on neuropsychiatric diseases in the first part of the nineteenth century. The main character of this opera, the Assyrian king Nabucco suffers from delirium. Psychic signs and symptoms attributed to Nabucco in Verdi's opera could have been influenced by a better knowledge of neuropsychiatric diseases in the nineteenth century. Furthermore, the representation of Nabucco's mental illness in the opera could also have been influenced by direct experiences of Verdi himself, who seems to have suffered from recurrent depressive episodes in that period, and for the rest of his life.