The word Mysteries defines medieval representations of sacred objects in vulgar language, certified in France since the XI century and performed during religious ceremonies in completion to the liturgical office. Similar to the theatrical plays, they originated as a consequence of the decadence of the classical Greek – Roman theatre and from the interruption of the theatrical activities during the entire medieval period. They became the mass-medias of that time and during the Renaissance period they slowly resumed the real and proper theatrical forms that established the bases of the modern theatre. On one hand there was the populations’ instinctive necessity to express its mixed religion of humanity, on the other hand there was the Church’s desire to educate people, mainly illiterate, with such spectacular forms that aroused interest. These forms, in this way, supported, in the open, the didactic – narrative function entrusted to sculptures and paintings inside churches. The phenomenon was common to many European areas, in its basic contents, but had different denominations according to the locality: mystПre (symbolic show) in France; auto sacramental (sacred representation) in Spain; passionsspiele (mystery of passion) in Germany; miracle-plays in England. During the centuries (XV – XVII), with the development of costumes, the rapid spread of magnificence exalted by the rich Renaissance courts, the ideological and psychological revolution of the Renaissance that distracted the spirits from the contemplation of a supernatural kingdom to address, instead, terrestrial goods, the scene effects took over the religious essence to the point of causing the infiltration of pagan elements in sacred dramas that sometimes seemed inconvenient and vulgar. From here the ban of the figurative representations, sanctioned in some councils held in France in the XVI century, and the substitution, in some Italian cities, of live groups with ligneous groups (ex. Mystery of the Holy Friday in Trapani) in which the intuitive force and the capabilities of the artist had to match the evocative and exciting effectiveness once promoted by live people. Since the XVI century, in Campobasso there is information, on the preparation of sacred representations on wooden stages placed near churches. Starting from the following century the main lay brotherhoods of the city, in order to celebrate the solemn festivity of Corpus Christi, got the habit of representing sacred scenes, in which the subject changed from year to year, on stretchers which were held on shoulders during the procession in front of the Holy Sacrament. The brotherhoods, around mid XVIII century, commissioned Paolo Saverio di Zinno, the sculptor from Campobasso, to project “machines” that would assure stability to the representations, so the scenes that were shown were always the same and the characters always had the same attitude, and for the achievement they entrusted the expert blacksmiths of Campobasso. In this way the Mysteries were created exactly as we know them today. According to an oral tradition not documented, twenty four Mysteries were created but six did not pass the tests and were never rebuilt. It is, instead, certain that eighteen Mysteries were created of which six were destroyed during the 26th July 1805 earthquake due to the collapsing of the buildings in which they were kept and the remaining twelve continued to parade along the streets of Campobasso during the procession on the day of Corpus Christi together with the Mystery of the Sacred Heart of Jesus, created in 1959 by the blacksmiths of the Tucci family of Campobasso on the bases of a drawing attributed to di Zinno. The six destroyed Mysteries represented The Body of Christ (“the big chalice”, so-called by the population for the presence of a big chalice), the Holy Trinity, St. Mary at the Cross, the Madonna of the Rosary (in which the main iron of the structure could rotate on itself when the Mystery was still), St. Stephen and St. Laurence. Since the XIX century, after the abolition of the brotherhoods, the Procession of the Mysteries has been organized by the Municipal Administration of Campobasso, which, as from 1997, is supported by the Mysteries and Traditions Association.