Childe Hassam

In the autumn of 1916, with the First World War raging in Europe and America not yet in it, New York started hanging flags. Fifth Avenue filled with them for one patriotic parade after another, and Childe Hassam, already the best-known Impressionist painter in the country, began climbing to upper-floor windows to paint the avenue as a river of banners. Over about three years he made some 30 of these flag pictures. The most famous, Allies Day, May 1917, shows the Stars and Stripes flying beside the British and French colours after the United States finally joined the war.

Hassam had spent decades learning to catch exactly this kind of shimmering, broken light. Almost every summer for close to 30 years he sailed out to Appledore, a rocky island off the New England coast, where the poet Celia Thaxter kept a famous seaside garden and a salon of writers and musicians. His paintings of her flowers against the blue Atlantic are among his most loved works.

Late in life he grew hostile to the modern art arriving from Europe and argued for a purely American painting. He left the several hundred works still in his studio to the American Academy of Arts and Letters, with instructions to sell them and fund prizes for younger artists.