How did Julie; or, The New Eloise help establish the sentimental novel?

Jean-Jacques Rousseau established the modern French sentimental novel, or novel of sensibility, with the immense success of his 1761 work, Julie; or, The New Eloise.12

The novel helped define the genre through several key characteristics:

• Exaltation of Emotion: In contrast to the rationalism of the Neoclassical period, the work prioritized feeling and spontaneity over reason. It featured a free expression of emotions and an extreme sensibility that deeply moved its contemporary audience.312
• Focus on Sympathy: The novel was rooted in Rousseau’s belief that moral development is fostered by experiencing powerful sympathies. It depicted a passionate attachment between the sexes that transcended the merely physical.34
• Influence on Romanticism: By emphasizing the "wisdom of the heart" and a profound responsiveness to nature, the book served as a precursor to the Romantic movement. It helped shift the focus of literature toward introspection and the exploration of the self.321
• Cultural Impact: Its popularity was unprecedented, influencing the spirit of the age and establishing a template for future romantic fiction.25