In the 1860’s Gustave Courbet (1819 - 1877) was in painting what Victor Hugo was in literature (Weekes, 75). Like Monet, he was a stubborn and independent man who had been attacked throughout his career for his choice of unorthodox themes from contemporary life throughout his career. 
His “Pavilion of Realism”, opened near the World’s Fair Exhibition of 1855, had marked him as the undisputed leader of Realism. Trained as a realist, Monet was certainly influenced by Courbet. Monet’s desire to depict life as he saw it derives from the realists’ rejection of historical imagery in favor of concentrating on recording the world around them. Monet similarly had no interest in the history of painting; he was interested in modern life, la vie moderne. The young artist’s attraction to contemporary subjects, such as that of Manet’s Déjeuner sur l’herbe, demonstrated his desire to depict real life in a straightforward manner, as Courbet did.
Courbet was most famous for his Burial at Ornans (1849), a staggeringly large depiction of a burial, measuring ten by twenty-two feet. Upon hearing of Monet’s own immense Déjeuner sur 
l’herbe project, Courbet went to visit him in Fontainebleau forest, no doubt to see who dared challenge his masterpiece. After Monet left Chailly to return to Paris to complete his painting, Courbet again came to visit him at his rue de Furstenberg studio in early 1866. There, Courbet made some suggestions on Monet’s Déjeuner, which the latter, receiving this advice from the realist master, felt obliged to accept (Isaacson, 30).
Although Monet never finished his enormous painting, Courbet’s influence on Monet is evident in the final canvas for his Déjeuner. The flatness of Monet’s forms is accentuated by Monet’s use of Courbet’s palette knife technique to apply paint in broad brushstrokes. Perhaps most telling is Monet’s inclusion of a figure closely resembling Courbet among the picnickers. He sits, imitating the pose of the left figure in Manet’s version, thus paying homage to the piece’s two greatest influences, as with his Déjeuner sur l’herbe Monet was simultaneously taking on both Manet’s subject and Courbet’s size. Although Monet did not finish his Déjeuner sur l’herbe it would appear he achieved his goal in the end, as he has since eclipsed both artists in fame.
Images:
Courbet, Gustave. Burial at Ornans, 1850. Musée d’Orsay, Paris.
Monet, Claude. Déjeuner sur l’herbe (detail), 1865. Musée d’Orsay, Paris.