Source: Oxford University Press
Term applied to the reaction against Impressionism led by Paul Cézanne, Paul Gauguin, Vincent van Gogh and Georges Seurat. It can be roughly dated from 1886, the year of the last Impressionist exhibition, to c. 1905, when Fauvism appeared and the first moves towards Cubism were made. While it was predominantly a French movement, there were related developments in other countries, which often occurred somewhat later. Post-Impressionism can be loosely defined as a rejection of the Impressionists’ concern for the naturalistic depiction of light and colour in favour of an emphasis on abstract qualities or symbolic content. It therefore includes Neo-impressionism, Symbolism, Cloisonnism, Synthetism and the later work of some Impressionists. The term was coined in 1910 by the English critic and painter Roger Fry for an exhibition of late 19th-century French painting, drawing and sculpture that he organized at the Grafton Galleries in London.
From Grove Art Online