A church at the site dedicated to St Bartholemew had existed since the 5th century; it was likely built atop an even older church and housed
Benedictine monks till the 16th century. The church was designed by
Giovanni Battista Falcetti with elaboration by
Agostino Barelli, and owes the awkward facade due to its construction in 1517 at the site of a palace begun by
Andrea da Formigine, commissioned by a member of the Gozzadini. The project, which is seen in the single-story portico along the exterior, was interrupted after the death of the patron, soon after completion of what became the side portico. In 1599, the church came under the leadership of the
Theatines, and in 1627, they ordained a complete restructuring of the complex by
Giovanni Battista Natali, called il Falzetta, and by
Agostino Barelli. In 1671 when Cajetan (
Gaetano), the founder of the Theatine order, was canonized, the church gained the added dedication. The bell-tower and final chapels were completed by 1694. ==Interiors==