Mary Victoria Cowden Clarke was the eldest daughter of the musician and publisher Vincent Novello and his wife, Mary Sabilla Hehl. She was raised with her 10 brothers and sisters in central London, where her parents enjoyed a lively social life among the writers, musicians and artists of the day, including Charles and Mary Lamb, Leigh Hunt and John Keats. Vincent Novello, who was born of an Italian father and English mother, was organist at the Portuguese embassy chapel in South Street, Grosvenor Square from 1797 to 1822, and from 1812 pianist and conductor of the Italian opera in London. His publication of a collection of sacred music in 1811, much of it unfamiliar to the British public, in effect inaugurated the Novello music publishing firm, which his son Alfred took to full commercial development.