The origin of the church is earlier than the first half of C.VIII. One says that some Basilian nuns stopped by here on their way from Costantinopoli, while they carried the body of San Gregorio Nazianzeno and many relics of martyrs. The oriental Catholic church has, probably for this reason, an Antiochene ritual and was annexed to a monastery of Benedictine nuns that was founded around 750 by Pope Zaccaria.
Built by the hand of Giacomo della Porta, Carlo Maderno and Francesco Paparelli, in 1668-1685 it was turned conformingly with the taste of the time by Giovanni Antonio De Rossi, author of the architectural decoration of the atrium and the facing courtyard, made wider via an illusion. It has a square plan with a Greek cross and an elliptical tambour-less dome. The peculiarity of the church consists of the numerous chapels, all richly decorated. On top of the altar there is the painting of a Madonna dated C.XII, where the church gets its name.
The interior is architecturally complex, it has a Borrominesque elongated octagonal nave, with two chapels at each flank. To the right is the main chapel dedicated and holding the relics of Saint Camillus. In this Chapel the vault was frescoed (1744) by Sebastiano Conca. The church also has a Christ, Virgin, and St. Nicolas of Bari by Baciccia and a San Lorenzo Giustiniani with Infant Jesus by Luca Giordano. The rococo sacristy is elaborately painted, stuccoed, and decorated with polychrome marble.
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SANTA MARIA IN CAMPO MARZIO