From the Francini family of Florentine musicians that had come to France under Henry IV of France, Jean-Nicolas married Jean-Baptiste Lully's eldest daughter Catherine-Madeleine Lully on 18 April 1684, in the presence of Louis XIV.
He also authorised the opening of opera houses in France's provincial cities – Lyon, Lille, Bordeaux, Rouen.
Not himself a composer, he commissioned others to renew the operatic repertoire, putting on works by Louis Lully, Pascal Collasse, Elisabeth Jacquet de la Guerre and Marc-Antoine Charpentier.
He was poor at management, however, and was forced to go into debt to keep the institution afloat, finally leading to the selling of his privilege in 1704 in favour of Pierre Guyenet.
However, despite the king's support, the opera house was still not in profit when he ceded his place to André Cardinal Destouches in 1728.