The dedication is to the Purification of the Virgin Mary, but is commonly ascribed to Saints Bassus and Timothy, patrons of the city.
There is a reference to a larger church dedicated to the Virgin Mary (Ecclesia Sanctae Matris) in 1037, a few years after the synod held by Pope John XIII in 969, which was attended by the first bishop of Termoli.
The present Romanesque building was constructed in the 12th and 13th centuries on the site of its predecessors, and is attributed to Alfano of Termoli, perhaps the same who made the ciborium in Bari Cathedral.
In the lower part are seven blind arcades with double mullioned windows, each different from the others, and decorated with acanthus leaves and human figures.
The inscription in one of the lunettes of the double window commemorates Stasio Grimaldi di Giovanni, who contributed financially to the building works of the cathedral.