Pope St Damasus I dedicated his life to establishing and strengthening the Church after the great persecutions, and took much care over the restoration of the Roman catacombs and the proper burial of the martyrs there, including Marcellinus and Peter.
As a boy, Damasus had heard the story of these martyrs from their executioner. Marcellinus was a priest, Peter was not. They were beheaded during the emperor Diocletian’s persecution, and buried on the Via Labicana outside Rome.
After the persecutions, a basilica was built over the site of their tomb.
Saints Marcellinus and Peter (- 304)
Wall painting (4th century) from the catacomb of Marcellinus and Peter on the Via Labicana, showing Christ between Peter and Paul, and below them the martyrs Gorgonius, Peter, Marcellinus, and Tiburtius.