The license for its foundation is dated December 6, 1640, granted by King Philip IV of Spain to Baroness Maria Sarzana, widow Ventimiglia, administrator of the feudal, urban, and rural estates of the young Francesco Graffeo, Baron of Serra di Falco, Salacio, and Grotta dell’Acqua. Of the three fiefs at her disposal, Donna Maria Sarzana Ventimiglia chose Serra di Falco. A notarial deed of sale, the memoriale of Donna Antonina, confirms the choice, mentioning cum Casalotto existing in said fief Serra di Falco. With this name Casalotto the work begun (and later abandoned) by Donna Maria is indicated, due to the financial troubles and debts accumulated over the years by the Graffeo family. The fiefs mentioned above were later purchased at auction by lawyer Leonardo Lo Faso on May 15, 1652.
In the following months, on the “Cozzo”—today Piazza San Francesco—Baron Leonardo Lo Faso, who only received the title of duke in 1666, built the first Mother Church (today popularly called San Francesco) and the Baronial Palace. The works on the first church ended three years later, and on the third Sunday of August 1656 it was opened to worship and consecrated to Saint Leonard Abbot of Noblac.
After a few decades, the construction of a new ducal palace was decided in the lower area—not far from the first one—where it still stands today. The street where the ducal residence was built was called “Strada del Palazzo,” later renamed “Via Duca” in the early 1900s. In the early 1700s, the construction of the cemetery chapel began, originally consecrated to the Holy Souls of Purgatory.
In the 1740s, the construction of the new Mother Church began, again dedicated to the patron Saint Leonard—remarkable for its size and interior decoration. Ten years later, the first cemetery chapel, dedicated to Santa Maria delle Grazie, was demolished to make room for a new church dedicated to the Immaculate Conception. In the early 1800s, devotion to the Virgin Mary grew stronger, so much so that in 1817 the first stone of the Collegio di Maria was laid, with an adjoining church dedicated to Our Lady of the Seven Sorrows.