Spolia

Spolia (Latin, 'spoils'), the repurposing of building stone for new construction, or the reuse of decorative sculpture on new monuments, is an ancient and widespread practice whereby stone that has been quarried cut and used in a built structure, is carried away to be used elsewhere. The practice is of particular interest to historians, archaeologists and architectural historians since the gravestones, monuments and architectural fragments of antiquity are frequently found embedded in structures built centuries or millennia later.

Archaeologist Philip A. Barker gives the example of a late Roman period (probably 1st century) tombstone from Wroxeter that could be seen to have been cut down and undergone weathering while in use as part of an exterior wall, then, possibly as late as the 5th century, reinscribed for reuse as a tombstone.

The practice was common in late antiquity. Entire obsolete structures, including underground foundations, are known to have been demolished to enable the construction of new structures. According to Baxter, two churches in Worcester (one 7th century and one 10th,) are thought to have been deconstructed so that their building stone could be repurposed by St. Wulstan to construct a cathedral in 1084. And the parish churches of Atcham, Wroxeter, and Upton Magna are largely built of stone taken from the buildings of Viroconium Cornoviorum.

Roman examples include the Arch of Janus, the earlier imperial reliefs reused on the Arch of Constantine, the colonnade of Old Saint Peter's Basilica; examples in Byzantine territories include the exterior sculpture on the Church of Panagia Gorgoepikoos in Athens); in the medieval West Roman tiles were reused in St Albans Cathedral, in much of the medieval architecture of Colchester, porphyry columns in the Palatine Chapel in Aachen, and the colonnade of the basilica of Santa Maria in Trastevere. Spolia in the medieval Islamic world include the columns in the hypostyle mosques of Kairouan, Gaza and Cordoba.

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