Ravenna mosaics

Italy has the richest concentration of Late Antique and medieval mosaics in the world. Although the technique is especially associated with Byzantine art, and many Italian mosaics were probably made by imported Greek-speaking artists and craftsmen, the numbers of significant mosaics remaining in the core Byzantine territories are surprisingly few. This is especially true for the centuries before the Byzantine Iconoclasm of the 8th century.

"Early Roman mosaics belonged to the floor"; except in Nero's Domus Aurea, there is little evidence of ambitious wall mosaics before the Christian period, even at Pompeii and surrounding sites, where their chances of survival were better than elsewhere. The famous Alexander Mosaic (c. 100) from Pompeii, arguably the finest pre-Christian mosaic to survive, was a floor, and the main use of vertical mosaics there is in places unsuitable for frescos, such as fountains, baths and garden architecture including the very popular nymphaeum.

Sumptuous floor mosaics found by archaeology in villas continue into the Late Antique period, including those at the Villa Romana del Casale at Piazza Armerina and the Gladiator Mosaic, both of about the 320s. In contrast, the floors of Early Christian churches contained very little figurative art, no doubt largely because it was considered inappropriate to walk on sacred images. The church floors are mostly geometrical, with small images in compartments of animals and the like, whereas the most important villa floors may contain huge scenes with many figures. The major surviving exception is the floor of the Cathedral at Aquileia, which is the earliest large area of Christian mosaic in Italy, dating to 314-18. This has large images of Christian symbols such as are seen in the Catacombs of Rome, including the Good Shepherd and Jonah and the whale, but no direct depictions of Christ. The Tomb of the Julii, under and pre-dating St Peter's, Rome also has symbolic images, including a famous one of Christ as the sun god in his chariot. This subject also has the gold background not usually seen until the end of the 4th century.

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