However, what most of his pasticheurs pick up on, certainly the contemporary ones, is not the neo-platonic themes of the Primavera (c.1482) or The Birth of Venus (c.1485) but Botticelli as cliché. Admittedly, exactly what those two paintings in particular are about remains uncertain but Warhol, for example, turned Venus into a multi-version silkscreen just as he did any other celebrity, from Elizabeth Taylor to Jackie Onassis. David LaChapelle reworks the painting as an eroticised festival of camp, while in Untitled #225 Cindy Sherman herself takes the role of Botticelli’s platonic mistress Simonetta Vespucci, the supposed model for Venus and the woman at whose feet he asked to be buried in the church of Ognissanti in Florence.

These artists play, with a knowing air, on Botticelli’s fame and the familiarity of his work. Rossetti and the Victorians didn’t have that luxury, or self-indulgence, and so adopted his mood. They looked hard at the works and if the meaning of his classical paintings was elusive their atmosphere was not. The goddess of spring of Primavera reappears in their work in all her floral sweetness but without her distracting attendants. They took too the way Botticelli infused his works with the mood of a dream and they recognised his pioneering spirit as the first Renaissance painter to treat classical subjects on the same scale and with the same seriousness usually given to religious works.

That Botticelli was not a mere decorative lightweight is reinforced by Botticelli and Treasures from the Hamilton Collection at the Courtauld Gallery (until May 15), an exhibition that includes 30 of the 92 surviving drawings Botticelli made to illustrate a printed edition of Dante’s Divine Comedy. An anonymous author, writing around 1540, said that Botticelli “painted and illustrated a Dante on sheepskin for Lorenzo di Pierfrancesco de’ Medici which was held to be something marvellous”. Lorenzo was the owner of both The Birth of Venus and Primavera and the Dante drawings are indeed something marvellous — large-scale, horizontal in format and both inventive and faithful to the text. If it was Dante Gabriel Rossetti who helped resurrect Botticelli, it was, appropriately, Botticelli who helped fuel the 15th-century revival of interest in Dante Alighieri.

The legacy of another hugely influential artist is the topic of the National Gallery’s new exhibition Delacroix and the Rise of Modern Art (until May 22). Van Gogh, Gauguin, Monet, Whistler, Cézanne, Matisse and Picasso were just some of the painters who acknowledged their debt. As Cézanne commented, “We all paint in Delacroix’s language.”

The language they learned was not just one of fluid handling and colour harmonies but of his disdain for the official art world. While the exhibition pitches Delacroix (1798-1863) as a prototypical modern artist, he saw himself as an upholder of tradition. “I am a pure classicist,” he avowed and he was indeed the last major 19th-century painter to tackle art’s great themes — religion and mythology. If the younger generation couldn’t or wouldn’t follow him there they had less trouble with his dictum that “the first merit of a painting is to be a feast for the eye.”