This book is an interdisciplinary study exploring the broad relevance of music in Franciscan hagiography, art, theology, philosophy, and preaching between the founding of the Order in 1210 and 1300-a period covering their rapid ascendancy in medieval society as an Order of clerics. The book covers representations of music in visual and literary hagiography, the inspiration of Pope Innocent III, and the formative writings of William of Middleton and David von Augsburg. Later chapters examine the science and practice of music and its relevance to the ministry of preaching through the writings of Robert Grosseteste, Roger Bacon, Bartholomaeus Anglicus, and Juan Gil de Zamora.