The world wars force artists to grapple with destruction and savagery, challenging conventions and the old imperial order, while those fleeing war bring new ideas to Britain. Contemporary war photographer Oliver Chanarin traces the story of William Orpen's subversive protest image, To the Unknown British Soldier in France, picturing a lone draped coffin amid the magnificence of the Palace of Versailles where peace delegates met in 1919, while artist Ryan Gander examines how sculptor Barbara Hepworth tried to make sense of war by reaching for beauty in abstract human forms and Denzil Forrester looks ahead to the post-colonial aftermath of war