Post-Impressionism developed in the 1880s-1900s as an extension of Impressionism. While Impressionism depicted idyllic scenes using vivid colors and brushstrokes, Post-Impressionism was more emotionally charged and emphasized form. Key Post-Impressionist artists included Paul Cézanne, Vincent van Gogh, Paul Gauguin, and Georges Seurat. Each developed unique styles, with Cézanne bringing structure to Impressionism, van Gogh using color and brushstrokes to depict mood, Gauguin seeking primitive expression, and Seurat exploring color science.