"Tapiola", Sibelius's last major orchestral work, was commissioned by Walter Damrosch for the New York Philharmonic Society where it was premiered on 26 December 1926. It is inspired by Tapio, a forest spirit from the "Kalevala". To quote the American critic Alex Ross, it "turned out to be Sibelius's most severe and concentrated musical statement." Even more emphatically, the composer and biographer Cecil Gray asserts: "Even if Sibelius had written nothing else, this one work would entitle him to a place among the greatest masters of all time."