The Dulcinians, or Dulcinites, and Apostolic Brethren were inspired by Franciscan ideals and influenced by the Joachimites but were considered heretical by the Catholic Church.
He published the first of his letters explaining his ideas about the epochs of history based on the theories of Gioacchino da Fiore.
At the beginning of 1304, three Dulcinians were burned by the Inquisition, leading Dolcino to evacuate the community to the west side of the Sesia valley, near his native Novara.
They descended the mountain to pillage and kill the people in the valley, responsible in their eyes for not defending the group against the episcopal troops.
The main concepts of the Dulcinians were: Fra Dolcino was inspired by the millenarist theories of Gioacchino da Fiore.