Introduced to landscape painting through his cousin Pau de Saint-Martin (q.v.), Rousseau entered the studio of Jean-Charles-Joseph Rémond (1795-1875) in 1826 and was later taught by history painter Guillaume Lethière (1760-1832). The young artist copied the works of Claude Lorrain (1600-1682) and Dutch seventeenth-century landscape painters at the Louvre, and he was intrigued by contemporary painters such as Constable (q.v.) and Bonington (q.v.). His foremost interest, however, was the study of nature. In 1830 he traveled extensively through the Auvergne and was much inspired by the wilderness of this region. Scheffer (q.v.), who admired Rousseau's nature studies from this period, introduced him to the Paris art circles of Charles Baudelaire and Delacroix (q.v.). In the early 1830s Rousseau also met Corot (q.v.) and became very close friends with Dupré (q.v.). Rousseau exhibited at the Salons of 1831 and 1833-35. After 1836 he began to travel extensively throughout France, notably to the forest of Fontainebleau and to Barbizon, where he would return every year and become the leader of the group of romantic-naturalist artists, the so-called Barbizon School. In the 1850s he also became increasingly involved in the movement to preserve the forest of Fontainebleau from industrialization. From 1836 until 1841 all of Rousseau's works were refused at the Salon because the jury advocated a more classicizing landscape painting. As he was also often passed over for official honors, the artist became known as "le grand refusé" and abstained from showing his work at the Salon most of the 1840s. After the 1848 revolution, the new regime under Napoleon III rated his work more favorably, even granting him a first-class medal at the 1849 Salon, so he no longer had to submit his work to the jury. Yet Rousseau had not been awarded the Legion of Honor, an even stronger insult when Dupré received it. In the early 1850s Rousseau befriended Millet (q.v.), and the two often worked together in Barbizon. Rousseau's international breakthrough occurred at the 1855 Exposition Universelle, where his work was exhibited in a gallery that he shared with Decamps (q.v.). Throughout his career, however, the sale of his work was unstable, partly because not showing regularly at the Salon limited his exposure. The artist therefore even had to organize two auctions (1850, 1861) of his works in order to make money, but the results were disappointing. Rousseau exhibited thirteen paintings at the Exposition Universelle of 1867 and figured as president of the jury. Yet because of his animosity with Comte de Nieuwerkerke, directeur-général des musées impériaux, the artist only received a grand medal and not the anticipated highest rank, Officer of the Legion of Honor. The lesser medal was awarded only after heavy protest from Rousseau's friends, five months before his death, and Nieuwerkerke had the last word, refusing to honor the artist with a posthumous retrospective as would have been expected. Although Barbizon painters such as Rousseau are noted for their study from nature, many worked on their larger canvases in the studio. And even though his art was still rooted in a romantic spirit, Rousseau's plein-air studies and his preoccupation with the rendering of specific light effects were instrumental for the development of impressionism.