Ubertino of Casale was an Italian Franciscan and one of the leaders of the Spirituals, the stricter branch of the Franciscan order.

The Franciscans are a group of related mendicant religious orders of the Catholic Church. Founded in 1209 by the Italian saint Francis of Assisi, these orders include three independent orders for men, orders for nuns such as the Order of Saint Clare, and the Third Order of Saint Francis open to male and female members. They adhere to the teachings and spiritual disciplines of the founder and of his main associates and followers, such as Clare of Assisi, Anthony of Padua, and Elizabeth of Hungary. Several smaller Protestant Franciscan orders or other groups have been established since late 1800's as well, particularly in the Anglican and Lutheran traditions.