Monet began his iconic large-scale images of his water pond in Giverny at a time of personal turmoil and sadness in 1914.   Then in his mid-seventies, he was one of the world's most famous and successful painters.  However, he had virtually given up painting following the deaths of both his wife and his eldest son,and a diagnosis of cataracts.   Nonetheless, it was during this period of sorrow, ill-health and creative uncertainty that - as the guns roared on the Western Front - he began the most demanding and innovative paintings he had ever attempted.   This lecture examines the personal and aesthetic motivations behind Monet's immense canvases and their legacy in twentieth-century art.