You may think there were many people called Hildegard von Bingen: the one who catalogued the animals, birds, fish, plants, trees and precious metals of her native German Rhineland; the one whose medical theories are still valued by holistic therapists today; the one who invented her own, mysterious language of 900 words, its intention a continuing debate among scholars. Perhaps more famous is the writer, theologian and abbess, whose bold, arresting visions – many depicted in illuminated manuscripts – reflected her own fervent beliefs; who founded her own monastery; who stood up to monks, bishops, popes and emperors across Europe, the scourge of a corrupt Church, earning her the name ‘Sibyl of the Rhine’.

Finally, there is Hildegard the musician: one of the first named composers and the woman who concerns us here. We cannot...