In 1549, Joachim du Bellay published 'La Défense et illustration de la langue française', a seminal work advocating for the enrichment of the French language. Du Bellay argued for the importance of drawing inspiration from classical models to elevate French literature. His ideas contributed to the Renaissance movement in France, fostering a renewed appreciation for the French language and its literary potential.

Joachim du Bellay's 1549 publication of 'La Défense et illustration de la langue française' served as a manifesto for the Pléiade group, elevating the French language to a status equal to Latin and Greek. This movement encouraged the use of odes and sonnets in French poetry, significantly shaping the national literary identity and inspiring poets like Ronsard.