Santa Marta al Collegio Romano is a deconsecrated 17th century Baroque convent church at Piazza del Collegio Romano 5, opposite the college in the rione Pigna. Picture of the church on Wikimedia Commons are here. There is an English Wikipedia page here.
The dedication was to St Martha.
The church was founded by St Ignatius Loyola at the beginning of the 16th century, together with a convent of nuns who were to minister to malmaritate. These were described as married women who went out alone looking for entertainment or earning opportunities, mostly of a sexual nature. Predictably this mission did not last very long, and the complex was passed on to a community of Augustinian nuns in 1540.
They rebuilt it in the Baroque style in 1673 using the dowry of Eleanora Buoncompagni, one of the monastic community who came from a noble family. The architect was Carlo Fontana.
In the French occupation the church was used as a Masonic lodge, and in 1873 was confiscated by the State together with almost all the other convents in Rome.
The monastery became the headquarters of the city police, and the church was formally deconsecrated in 1910. After neglect and use as the police gym, the church building was restored and is now a hall for exhibitions, concerts and conferences -the Sala Convegni Santa Marta.
The convent was a large one. The main entrance was in the Via San Stefano del Cacco, and this led into a large rectangular cloister with arcaded walkways on three sides (not the north). There was a formal garden in the garth, with a fountain. The church was at the north-east corner of this cloister. The kitchen court was next to the Via della Gatta, and a side entrance from this street led to this before running through to the main cloister.
The restrained church façade has the entrance framed by a pair of Doric columns in the round, supporting a frieze of stylized fasces supporting a triangular pediment. There is a pair of Doric pilasters on either side, with a narrow rectangular window between each pair. These support a full entablature, with architrave, a frieze in the same style as that above the door and a projecting cornice. Above that, the upper storey of the façade has four
pilasters without capitals running up to the gabled roofline. There are three rectangular windows, the middle one larger and with a stone frame fitting snugly between the inner pilasters. Very unusually, there is a broken triangular pediment below the actual roofline and laid over the four pilasters, into which the abovementioned frame inserts and which contains a 17th century fresco by an anonymous artist.
The rectangular interior is small, having a single nave of three bays and a semi-circular apsidal sanctuary. There are three chapels on each side, occupying shallow arched niches.
The décor is very rich in stucco, gilding and polychrome marble work but most of the paintings have been removed. This is a tragedy, as the church had an important collection.
The main body of the church has three bays, with the chapel arches separated by wide Corinthian pilasters with notched corners and gilded capitals. These support an entalature which runs around the entire interior, and which has a gilded architrave and cornice. Above the side arches are large rectangular windows, three on each side.
The entrance doorway is flanked by a pair of doubletted pilasters in shallow relief, and either side of the central window above the entablature is a large stucco angel holding the end of a flower festoon. These, and the other stucco work, are by Leonardo Lambardi. The entrance looks as if it had a small organ gallery above it originally.
The side chapel arches have archivolts springing from imposts on strap corbels (an unusual design feature), and in the spandrels are more stucco angels.
The marble floor is recent.
The nave ceiling has an interesting and complex design. It is basically barrel vaulted, with triangular lunette embrasures above the windows which are edged by wide ribs decorated with festoons. The vault is divided into three by two wide transverse arches in between the bays, also with festoons on their archivolt.
The ceiling vault of each bay has an elliptical tondo occupying its entire length, with a wide frame in the same style as the lunette ribs which touch it on each side. The three tondi are frescoed with scenes from the life of St Martha, and are by Baciccio who painted the ceiling of the Gesù, and who received that commission as a result of his work here.
The tondo nearest the apse has an interesting depiction of St Martha with a dragon. This is an allusion to the unhistorical legend that she, with SS Mary Magdalen and Lazarus, travelled to Provence in France after the resurrection. The dragon is called the Tarasque. The central tondo shows her apotheosis, and the one nearest the entrance has her performing a miracle.
The fresco work in the triangular ceiling panels surrounding the tond is by Paolo Albertoni, and depict allegorical figures. The actual lunettes contain large scallop shells in stucco.
The sanctuary is a semi-circular apse. It is entered through a triumphal arch which as a pair of pilasters in the same form as the nave ones, except revetted in a pink blotched marble. The corners flanking these have horizontally stepped pilaster strips. The archivolt springs from the entablature, and is deep with several orders of molding. On it is a stucco group of angels with a large scroll.
The apse has an oval tondo frame for the former altarpiece, supported by a pair of stucco angels and flanked by a pair of columns in the same marble fronting a pair of pilasters. These are flanked in turn by two rectangular picture frames supported by more angels.
The apse conch above the entablature has three tondi separated by very wide ribs. Two are windows, but the central one has a stucco relief.
The former main altar was free-standing, and has been removed. Below the central tondo frame is a doorway leading into the former nuns' choir.
The pictures that were formerly here were: Central, Our Lady with SS Martha and Mary Magdalen by Guillaume Courtois; to the sides, The Three Marys at the Tomb by Luigi Garzi and a work by Fabio Cristofari.
The side chapels are listed in anticlockwise order, beginning to the right of the entrance. The dedication and a description of the former altarpiece are given for each.
First right: Transfiguration, with a depiction by Alessandro Grimaldi (1621-83).
Third left: Our Lady, with a depiction of her by Giacinto Gimignani.
The former nuns' choir is now a lecture hall, and the vaulted chamber is whitewashed. One end has three damaged 16th century frescoes which show the Madonna and Child in the middle, and her Annunciation and Visitation to the sides.