The friars of the strict Observants settled in Barga in 1434: the vast consent obtained by the founder, Fra Ercolano, throughout the entire Lucca area had motivated Papal authorization of the founding of two monasteries in Garfagnana: the first at the Parish Church of Fosciana, and the second here, in Barga, run by four followers of Ercolano, two of which were destined to become blessed souls. In 1471 the community was permitted to leave the small monastery in Nebbiana, for a location closer to the inhabited area. Having bought a piece of land on the road from Fornaci to Barga, including the small church of S. Maria delle Grazie, the new buildings were finished before the end of the century thanks to the contributions of the local population and authorities. The present day church preserves its original plan, with a single nave stressed by bays with reinforced cross vaults; it is thought to have undergone new building works during the 16th century that made a re-consecration necessary in 1572. The outlying buildings, on the three sides of the cloister adjacent to the church, were modified many times over, also due to the suppression of the Monastery in 1810 and the setting up of a hospital in the abandoned premises, which had since become the property of Barga Town Council. From 1859 the Opera Pia of S. Francesco’s Hospital, founded in 1848, made necessary the presence of a brotherhood of Capuchin monks to assist the sick. Enlarged during the 20th century, these premises still include a hospital.
Also belonging to the period of the re-founding of the monastery is the valuable and extensive group of Florentine glazed earthenware that enriched the church between 1480 and 1515: many of which can still be found today.