Marcolino Amanni was born in 1317 at Forlì in the Papal States (Emilia-Romagna). At the age of 10 (1327), he entered the Dominican Order at the Convent of San Domenico at Forlì.
Marcolino spent the 70 years (1327–1397) at the Forlì Dominican Convent — undertaking the hidden vocation of the Dominican simple-brother, without the public preaching or institutional office that characterized his Dominican contemporaries.
His personal vocation was distinguished by the quiet self-effacement: spending his entire life in the choir-office, the refectory-and-cell simple discipline, and the personal charity to the Forlì poor at the convent-gate.
During his lifetime, Marcolino's hidden sanctity was so invisible that his fellow Dominicans regarded him as unremarkable — only after his death did the spontaneous pilgrim-cult at his tomb reveal his previously hidden sanctity.
He died at Forlì on January 24, 1397 at the age of 80.

