Favourite disciple, secretary and confessor of St. Francis of Assisi. The dates of his birth and of his becoming a Franciscan are not known; but he was one of the small group of most trusted companions of the saint during his last years. After Franciss death Leo took a leading part in the opposition to Elias: he it was who broke in pieces the marble box which Elias had set up for offertories for the completion of the basilica at Assisi. For this Elias had him scourged, and this outrage on St. Franciss dearest disciple consolidated the opposition to Elias and brought about his deposition. Leo was the leader in the early stages of the struggle in the order for the maintenance of St. Franciss ideas on strict poverty, and the chief inspirer of the tradition of the Spirituals on St. Franciss life and teaching. The claim that he wrote the so-called Speculum perfectionis cannot be allowed, but portions of it no doubt go back to him. A little volume of his writings has been published by Lemmeus (Scripta Iratris Leonis, 1901). Leo assisted at St. Claras deathbed, 1253; after suffering many persecutions from the dominant party in the order he died at the Portiuncula in extreme old age.
All that is known concerning him is collected by Paul Sabatier in the Introduction to the Speculum perfectionis (1898). See St. Francis.