It is unusual for an exhibition of unknown artists to open with critical acclaim and draw crowds to a major gallery. What is more remarkable is that few of the artists received formal tuition, none belonged to a movement or painted commercially and they did not expect their work to be seen by an audience. The artists were mentally ill people residing in asylums throughout Europe whose work was collected between 1918 and 1921 by the German psychiatrist and art historian Hans Prinzhorn (1886–1933).