The basilica marks the burial place of the great convert and Apostle to the Gentiles, St. Paul.
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Introduction
As early as A.D. 200, the burial place of the great Apostle in the Via Ostia was marked by a cella memoriæ, near which the Catacomb of Comodilla was established. Constantine, according to the "Liber Pontificalis", transformed it into basilica; in 386 Theodosius began the erection of a much larger and more beautiful basilica, but the work including the mosaics was not completed till the pontificate of St. Leo the Great.
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