Jean-Jacques Rousseau was a Genevan philosopher of the Enlightenment whose political ideas influenced the French Revolution, the development of socialist theory, and the growth of nationalism. Rousseau also made important contributions to music both as a theorist and as a composer. With his Confessions and other writings, he practically invented modern autobiography and encouraged a new focus on the building of subjectivity that would bear fruit in the work of thinkers as diverse as Hegel and Freud. His novel Julie, ou la nouvelle Héloïse was one of the best-selling fictional works of the eighteenth century and was important to the development of romanticism.