Music is a key motif in BITTER GREENS, from the use of musical notations to name each section of the book, to the staging of the opera at the end of the book, in which my 'Maiden in the Tower' character, Margherita, sings.
I thought you might be interested to know what is true in the musical references in the novel:
The Ospedale della Pietà in Venice really did take in abandoned girls and train them to be extraordinary singers and musicians.
Young boys in Renaissance Italy were sometimes castrated against their will to preserve their soprano voices.
Jean-Baptisete Lully, the court composer for Louis XIV, really did die after banging his toe with his staff while conducting a Te Deum in honour of the king's recovery from illness. The wound turned gangrenous, but Lully refused to have his toe amputated and the gangrene spread, resulting in his death on 22 March 1687.
Jean-Baptiste Lully, the court composer at Versailles
The first opera to ever be performed really was ‘Euridice’, written by Jacopo Peri and performed in Florence in October 1660 to celebrate the forthcoming marriage of Henri IV of France and Maria de Medici. One of the castrato who sang in that opera was named Giovanni Magli, but as far as I know he was never bodyguard to a witch.
The interior of the Pitti Palace in Florence