Tiburtine Sibyl
The Tiburtine Sibyl, also called Albunea, was a Roman sibyl, whose seat was the ancient town of Tibur (modern Tivoli).
The mythic meeting of Augustus with the Sibyl, of whom he inquired whether he should be worshiped as a god, was often depicted by artists from the late Middle Ages onwards. In the versions known to the later Middle Ages, such as the account in the Golden Legend, Augustus asked the Sibyl whether he should be worshipped as a god, as the Roman Senate had ordered. She replied by showing him a vision of a young woman with a baby boy high in the sky, and a voice from the heavens said, "This is the virgin who shall conceive the saviour of the world", who would eclipse all of the Roman gods. The episode was regarded as a prefiguration of the Biblical Magi's visit to the new-born Jesus and connected Ancient and Christian Rome, implying foreknowledge of the coming of Christ by the greatest of Roman emperors.
Whether the sibyl in question was the Sibyl of Tibur or the Greek Sibyl of Cumae is not always clear. The Christian author Lactantius identified the sibyl in question as the Tiburtine sibyl and gave a circumstantial account of the pagan sibyls, which is useful mostly as a guide to their identifications as seen by 4th-century Christians:
The Tiburtine Sibyl, by name Albunea, is worshiped at Tibur as a goddess, near the banks of the Anio, in which stream her image is said to have been found, holding a book in her hand. Her oracular responses the Senate transferred into the capitol.
— Divine Institutes I.vi