San Romualdo is a lost 17th century convent church that used to stand on what is now the south side of Via Cesare Battisti off Piazza Venezia. This street used to be known as Via di San Romualdo, in the rione Trevi.
This was not an old church, but replaced one on a different site that was. The precursor was a mediaeval church on the site of the present San Francesco Saverio del Caravita in the rione Colonna, which was known as San Niccolò de Forbitoribus. This dated back at least to the 12th century, as its first mention comes from 1192. This church was apparently seriously damaged by lightning striking its campanile in 1405, but was still functioning later that century.
In 1551 it was granted to the Camaldolese Order, which back then had not yet divided into various congregations. It was about to obtain a full-sized monastery in Rome, San Gregorio Magno al Celio, in 1573 but it was thought that a new central headquarters in Rome to represent all the monasteries of the order would be useful. Accordingly, the old church was demolished and rebuilt with a small monastery attached, and having a new dedication to St Anthony of Egypt. As with other such institutions in Rome before modern times, the monastery was often called an ospizio since one of its major functions was to accommodate monks of the order on visits to Rome (hospes is Latin for "guest").
Later the independent Camaldolese congregation of Monte Corona was formed, and this had its own church and monastery in Rome at San Leonardo dei Camaldolesi. The reason for the split was that the original order was of hermit monks living in community, and arguments arose as to whether the eremitic or the cenobitic ways of life should have priority. The Monte Corona monks argued for the former.
In 1631 the complex was bought by the Jesuits, and demolished in order to make space for an extension of their Collegio Romano. The Caravita Oratory was erected on the site of the old church, and the Camaldolese erected a completely new church and monastery nearby.
The monastery of San Gregorio was responsible for administering and staffing the institution, although the other monasteries of the order would have supported it with a cash subsidy.
The monastery was sequestered in 1873. The street was widened in 1878, as part of the works to make the Piazza Venezia the transport hub of the modern city, and the church was hence demolished.
The saint has been remembered in the Diocese, since the modern parish church of San Romualdo Abate a Monte Migliore has been dedicated to him. Whichever senior cleric was responsible had a sense of humour, since this is one of the most isolated and rural churches in the municipality and so appropriate for a hermit monk.
Before the late 19th century, the Piazza Venezia was much smaller than it is now. The Corso at the junction with the piazza was narrower on the east side than at present, and that line of buildings continued the frontage down the east side of the piazza. The Via di San Romualdo, as it was, consisted only of the present north pedestrian sidewalk and the northernmost traffic lane of the present Via Cesare Battisti. The south line of that lane marks the church façade.
When the Piazza Venezia was enlarged, the Palazzo Bolognetti on its east side was demolished somewhat later than the church and monastery. The present Palazzo delle Assicurazioni Generali which replaced has its western frontage further to the east than that of the old palazzo, making room for a much enlarged piazza. The massively widened Via Cesare Battisti swallowed most of the site of the church and monastery.
What this now means is that the site of the church is at the north-west corner of the Palazzo delle Assicurazioni Generali, mostly in the roadway. The corner of the building impinges on the site of the presbyterium, and the body of the church was to the west and north as far as the traffic lane mentioned above.
This was a richly decorated little church. The layout was based on a Greek cross, with two large side chapels and a rectangular apse added to the presbyterium.
The monastery was to the east, and was laid out in three wings rather like a J on its side. The main wing was on the street, which had the entrance in its centre. This led into a long, very narrow cloister with an arcaded walkway running west to east from the church to the other wings of the monastery. On the other side of this was a courtyard, shared with secular buildings to the south.
The painting over the main altar, The Vision of St Romuald by Andrea Sacchi, is now in the Vatican Museums. It was taken there soon after the beginning of the 19th century, and replaced by a copy. The two side chapels were dedicated to the Crucifixion and the Visitation.