Camille Pissarro, 'Portrait of Cezanne', 1874

Camille Pissarro painted this portrait of Paul Cezanne in 1874 on one of his many visits to Pissarro’s home in Pontoise, outside Paris. The artist was 44 years old. Cezanne was nine years younger and in need of a mentor. They became close.

This is the portrait of a friend by a friend. Pissarro knew Cezanne well enough to be unsparing in his portrayal of his stocky, thickset figure. Cezanne sits in an upright chair and does not look at all comfortable. His nose and cheeks are weathered. His mouth is invisible under the tobacco-stained moustache and beard. His heavy coat is unbuttoned but not open. With a patterned scarf tucked around his neck, he is ready to go out into the winter weather. Black curls bubble out from under his soft, round hat with the brim turned down like a peak. These are the garments of an artist working outdoors.

Cezanne appears heavy and still, but the visible part of his hand seems on the point of lifting, the fingers almost twitching. Something or someone might have caught his attention. His black eyes flicker as he gazes out to a view waiting to be painted or a painting to be finished.

Throughout the early 1870s, each artist had a profound influence on the other’s work. The two men met often, to talk, to paint, to think about painting: how to take it forward, break the bounds, add to and mould its future each in their own way. They also learned from and respected the other’s experiments, discoveries and, no doubt, mistakes.

Two caricatures feature in the painting, one on either side of the sitter. On the right is Gustave Courbet, radical realist painter and political activist. He leans earnestly towards Cezanne as if encouraging him in his determination to find new ways of painting. The canvas in his hand shows Cezanne’s characteristic blocks of colour made by thick, diagonal brushstrokes. Comparing it with the bald head with its fringe of curls in Cezanne’s Self-Portrait, also in the National Gallery, gives us a glimpse of how his technique was beginning to develop.

On the left is Pissarro’s take on André Gill’s cartoon on the front page of L’Eclipse, the satirical journal. The conservative politician Adolphe Thiers strangles the proud French cockerel and plucks its feathers, following the fall of the Paris Commune. The inclusion of the cartoon confirms the rebellious political opinions of Pissarro and Cezanne.

Below Courbet hangs Pissarro’s painting, presumably, of Pontoise. The placing of the picture close behind Cezanne’s shoulder seems symbolic of a deep and supportive relationship that lasted for some years.

Later, their lives took different paths and they did not meet again. Pissarro became interested in the ideas of the Neo-Impressionists Seurat, Signac and others. Cezanne moved south to continue the exploration of his own vision. Yet Pissarro never lost his affection for Cezanne, or his interest in his work. When he died in 1903, his Portrait of Cezanne was still in his studio.