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From the Churches of Rome wiki:
According to legend, the church stands on a site where the Sts Peter and Paul and the Evangelists Luke and John stayed. Most important of these traditions is the one claiming that St Paul lived here.
The appellation comes from the ancient Roman street here, which roughly corresponds to the present Via del Corso.
The first Christian place of worship here was a 5th century oratory in the Roman building beneath the present church.
The upper level of the church was added in the 9th century.
The church was rebuilt in the late 15th century, c. 1491. It was renovated or rebuilt in the 17th century.
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The lower level has been excavated, and the remains of a large Roman warehouse, some 250 meters long, were found. The 5th century chapel and welfare center that were constructed in the building have been identified. There are murals from the 7th-9th centuries; they have been detached from the walls to preserve them. A relief by Cosimo Fancelli was plaved here in the 17th century, when the first excavations were carried out.
