A BYZANTINE RED AND GREEN PORPHYRY MOSAIC FRAGMENT, IN LATER MARBLE PANEL

On the 15th July 1823 a workman on the roof of the Basilica of Saint Paul Outside the Walls, Rome, started an accidental fire which destroyed almost the entire structure of the building which had managed to remain intact for almost 1500 years. Repair work would not begin for another two years and would not be completed until the 20th century. The basilica had been founded by Constantine I over the tomb of Paul of Tarsus - St. Paul, who had been beheaded under the rule of emperor Nero. The first altar was placed over the tomb by Leo I, and in the 6th Century Pope Leo the Great had placed a new altar above the earlier one, but still directly over the sarcophagus of St. Paul.