When British artists saw the first London exhibitions of American abstract painters such as Jackson Pollock and Mark Rothko in the late Fifties, they were astonished by the improvisatory freedom of their works, in which paint appeared to have been hurled on to the canvas without any preconceived ideas, and by the sheer size of the paintings. To artists raised in austerity Britain, the idea that you could do a painting 20ft-wide was a revelation.

Abstract expressionism exploded out of the US in the aftermath of the Second World War, signalling the shift of the art capital from Paris to New York. The paintings were completely abstract and they expressed big themes and emotions – tragedy, despair, the unconscious, angst of every description; feelings that were embodied not through imagery, but the intensity with which the painter got the paint on to the canvas.