The Istituto is the direct descendant of the the enormous old complex of the Ospizio Apostolico di San Michele, begun in the late 17th century on the Tiber in Trastevere. This became the main focus of the papal government's efforts in providing welfare initiatives for vulnerable people, especially the old and young. See San Michele a Ripa.
After the Italian government inherited responsibility in 1870, various departments began to be hived off until what was left was mostly a juvenile reformatory. This was merged with an orphanage called the Orfanotrofio di Santa Maria degli Angeli in 1928, and the two finally moved to a huge new complex in 1937.
The new premises were a Fascist initiative, and this is obvious from the architectural style. The project was initiated in 1934, and the architect was Alberto Calza Bini. He was also responsible for the church of San Francesco Saverio alla Garbatella.
The new istituto flourished after the Second World War as the city's largest centre for public assistance and charitable works, including residential non-medical care.
The layout of the core of the complex is approximately symmetrical, on a fan shape. What you see from the piazza is a monumental entrance block, behind which hides a large car park. Two main wings flank this at an angle, leaving room for V-shaped gardens with the narrower ends towards the rear. The chapel block is on the far side of the car park, and is connected to the side wings via curved covered corridors.
The chapel's design disguises its function. It amounts to a full-sized church of five bays, having a central nave with side aisles. The walls are in a pale yellow render, and the roofs are pitched and tiled.
The central nave protrudes very slightly above the side aisles, and has a gabled roof with a hip at each end. The narrow side aisles each have a single-pitched roof, but each aisle protrudes beyond the central nave at both ends and clasps the corners. Each end of the central nave is occupied by a block of sacristy or ancillary accommodation, with a roof of two triangular side pitches and a hip the top angle of which touches the wall of the central nave above.
Only one side of the nave has windows, a row of five large round-headed ones. The side facing the car park is, instead, occupied by a monumental entrance portico. This has a gabled roof, the ridge-line being as high as the eaves of the nave roof behind it, and boasts three huge and tall round-headed portals of the same size and completely undecorated. Above these is a one-line dedicatory inscription without any backing tablet.
The curving connecting corridors continue along the side of the chapel to meet this portico. In contrast to the rest of the building, they are in red brick and boast square portals separated by blind square piers.
The building stands over a crypt.
The interior is mostly in white, except for the dark wooden roof.
The narrow side aisles have galleries, with solid undecorated frontals. These are supported by six transeverse rectangular piers on each side, which run up to a pair of deep roofline entablatures. Each of these has a thin beaded architrave and a deep unmolded non-projecting cornice, between which is a frieze bearing an epigraph with sans-serif uppercase letters in relief (a very Fascist architectural design feature).
The floor has a rectilinear geometrical pattern in red marble.
The sanctuary is apsidal, although the apse is invisible from outside.
The altar stands on a three-stepped marble platform, and consists of a white marble mensa on a pair of green marble slab-piers. There is no frontal.
The apse has a gallery running round its curve, below the conch, and the void of this is broken by radial rectangular piers supporting the conch. The latter is in pale yellow mosaic.
Hanging at the back of the apse is a huge gilded and crowned glory, in which is a framed altarpiece. This in turn contains a smaller glory, focusing on a tiny icon. The ensemble is being venerated by a pair of large gilded angels on brackets protruding from the front corners of the apse.
Below the gallery, the apse wall is panelled in marble, the panels being in a grey-veined marble edged with dark pink.