We do not know exactly when the Carmelites arrived in Siena after leaving the Holy Land, but it was probably in the mid-1200s. With the help of the City, of the guilds and of wealthy citizens, they erected their church and the adjoining monastery where the friars, who consecrated their lives to penance and prayer, welcomed all those who wanted to join them in worshiping God and the Blessed Virgin Mother. Through the evangelization of the population living in this area, just outside the city walls, the Carmelites gained the respect and the official recognition by the municipality, who deemed it a religious institution entitled to support.
Many illustrious citizens of Siena joined the Carmelite Order, living for years in penance and prayer as the Blessed Franco da Grotti, whose reputation soon spread beyond the city’s borders from the thirteenth century .
In the sixteenth century four members of Sienese noble families succeeded each other as Generals of the Order: Bernardino Landucci, Eliodoro Tolomei, Mario Venturini and Giovanni Battista Faleri Caffardi, whose busts in plaster can be admired along the church walls .
The poor and pious friars of the Carmelite Order sustained themselves through private donations, the constant support of the City, alms, the sale of indulgences, masses in suffrage of the souls of deceased patrons and the offerings to the relics held in the church.
These takings enabled more than thirty friars to live in the priory during the seventeenth century.
With the reform of the Carmelite Rule by Saint Teresa of Avila, at the end of the 1600s a group of ten friars, after the necessary preparation in Rome, laid the foundations for the new Order of Discalced Carmelites even in Siena . Thus, while the friars of the Primitive Observance officiated in the church of San Niccolò al Carmine, the Reformed Carmelites built their own priory in the house and church of San Michele, where they remained until the Napoleonic suppressions.
Starting from the late eighteenth century the Order began to decline, with a progressive reduction in the number of friars. The situation plummeted during the nineteenth century with Napoleon’s suppression of religious orders, which forced the Carmelites to abandon their seat and move into the former Convent of the Holy Spirit in Siena. In 1821, when the religious buildings were returned to the various orders, the friars regain possession of their priory, perhaps with the Discalced Carmelites, until the final suppression established by the Kingdom of Italy in 1862.
The date in which the friars returned to San Niccolò al Carmine is uncertain, but they undoubtedly lived in the lesser cloister and celebrated Mass in the church from the 1980s until 2000, when the few remaining Carmelites joined the Mother House in Florence.