Camille Pissarro (1830–1903) was known as “the father of Impressionism” even in his own lifetime. He was the only artist to be represented at all eight Impressionist exhibitions between 1874 and 1886; although he was not generally considered the best of the school, his influence was profound. One of the many joys of “Pissarro: Father of Impressionism” at the Ashmolean Museum in Oxford is how it demonstrates this influence by displaying works, often outstanding ones, by the likes of Cézanne, Gauguin, Seurat, Signac, and Van Gogh, all of whom he met. Pissarro eschewed the traditional master-and-pupil approach of painting, being both a generous teacher and keen to learn from others in fraternal relationships. He was very much an evolving artist over his long career, as this exhibition makes admirably clear.