Santa Maria Immacolata del Istituto Scolastico Nazareth is a full-sized 19th century former convent church with a postal address at Via Cola di Rienzo 140 in the rione Prati.The dedication is to the Blessed Virgin Mary, under her aspect of the Immaculate Conception.
The large and impressive complex was begun in 1887 and finished in 1892 for a French congregation of sisters now known as the Religiosi di Nazareth (French: Religieuses de Nazareth) but then having the title Dames di Nazareth.
The sisters had a school here, but the present Generalate (headquarters) of the congregation is in Monteverde, at Via Caterina Fieschi 6. The Prati complex is now a private school known as the Istituto Scolastico Nazareth, in which the sisters are not formally involved.
The integrated complex was designed by Corrado de Rossi Re, and was his most important work in Rome.
The convent block runs west to east along the Via Cola di Rienzo, but the church is aligned along the Via Orazio north to south. As a result, the latter has no entrance façade, but is entered through a doorway on the Via Orazio which leads into a large vestibule. This acted as the convent chapel while the church was being built, and if you look at the Via Orazio façade you can see that the church was added on to the main convent block as the second phase of the overall building project.
The church is large, having a nave with no aisles but with an external semi-circular apse and a short campanile perched over the far left hand corner. The style is described as Lombardic; in Britain, it is Gothic in all respects except that the arches are round, not pointed. The building material is honey-coloured limestone in rather small ashlar blocks, and the nave and aisle roofs are pitched and tiled.
The street frontage of the church has a row of three identical large windows with a pair of drainpipe recesses between them. The frames have several orders of moldings, two of them with barley-sugar twists which is a feature of the overall design of the convent. The mullions are complex, of two storeys with three lights in each designed as attenuated arcades. In between these is a row of three wreaths containing Greek crosses, and at the top is a light in the form of a small rose window.
The nave roofline is decorated with a blind arcade with semi-columns on corbels and having cushion capitals. This decoration is repeated at the roofline of the apse, except there the semi-columns rest on a string course. Above the apse is a small quatrefoil window in a round molded frame.
The campanile has three storeys, the last half the height of the first two. The first is blank except for a recessed Greek cross on the two faces visible from the street, topped by a dentillate cornice. The second has an arcade of three open arches on each face, with columns and imposts. This is separated from the third storey by a simple molding. The latter storey has a row of three recessed Greek crosses on each face, and is crowned by a dentillate cornice. The roof is flat.
The vestibule has fresco work by Giovanni Capranesi (1852-1921), and the iron gates are by Lupacchini.
The main church looks very French Gothic in style (except for the round arches), and has a cross-vault springing from clustered attached columns with banded stonework. There is a triumphal arch, and a free-standing main altar under an impressive neo-mediaeval baldacchino with figurative carving. Walls and vaulting are frescoed in diaper patterns, and in the conch of the apse is The Immaculate Conception, showing Our Lady in a mandorla. This and the symbols of the Evangelists are by Bartolucci.