Under the Imperial protection during the IV and V centuries, monumental painting (represented by mosaics and catacomb frescoes) experienced great support in the Early Christian world, and during the sixth century such artistic boom continued well into the Middle Ages through the Byzantine art works and their Mediterranean diffusion. Rome, Naples, Milan and Ravenna retain the best examples of these decorative mosaics. Initially, there was a strong relationship between the iconography of these monumental mosaics and the paintings of the catacombs.
From the time of Constantine we only know the mosaics of St. Costanza and those of the Mausoleum of Centcelles. In St. Constanza the mosaics include themes with “profane” ornamentation covering the vaults of the annular ambulatory*. In these mosaics of St. Constanza there are geometric elements, scenes of cupids harvesting grapes, as well as portraits of Constantine and his wife. Rhombuses and crosses, interlacing belts, flowers mixed with objects in a harmonious mass, all define a fine taste very characteristic of this era.
The triumphant Christ, enthroned, presiding over a deeply hierarchical scheme appears in the mosaic of ca. 401-417 AD of the apse of St. Pudenziana. Here Christ is surrounded by the Apostles and by two figures as symbols of the churches of the Hebrews and Gentiles, all in an architectural landscape and a sky with a blue background dominated by a large triumphal Cross covered with gems. Here, the layout of the figures in the scene has profoundly changed and expresses clear ecclesiastical hierarchies.
This grandiloquent mosaic style developed during the V century, and had its highest expression in the mosaics of St. Maria Maggiore, that resemble the style of the paintings of the fourth century of the Catacomb of Via Latina, and in the famous Mausoleum of Galla Placidia in Ravenna. In the mosaics of St. Maria Maggiore, two great historical cycles decorate this temple. In the triumphal arch there are scenes from the life of Mary and the childhood of Jesus distributed in four overlapping areas; this represents an iconographic group so rare in the Western world because the representations of the childhood and passion of Christ were typical of the Coptic, Syrian and Byzantine East. The second historical cycle, based on scenes from the Old Testament, shows greater plastic vitality and extraordinary coloring, as seen in the mosaic that represents the crossing of the Red Sea, an issue also addressed in the paintings of Via Latina.
To follow the development of the decorative mosaics you have to go to Ravenna. It is in the mosaics of the Mausoleum of Galla Placidia that the artistic school of mosaics was originated and was also there where the Christian art of the mosaic was defined and whose development will ultimately led to the design of the great mosaics of San Vitale from the sixth century. The Mausoleum of Galla Placidia, completely covered with mosaics, is one of the most beautiful coloristic groups of the ancient world. Figurative elements combined with deep blue, green and gold tones of the plant and geometric ornamentation, create an atmosphere of beautiful unreality. In the lunettes* of the Mausoleum was represented a Shepherd of great Hellenistic finesse sitting holding the Cross among his lambs, as opposed to another panel with St. Lorenzo facing his martyrdom. The four walls of the dome contain eight Apostles, rigid and schematic, less naturalistic, beginning a style frequently used later in other mosaics in Ravenna. All the scenes and figures are immersed in deep blue skies with geometrized stars in the vaults, accompanied by representations of deer seeking water from the Fountain of Life. All these scenes are framed with garlands of vines, wreaths of flowers and geometric bands, all in unique harmony.
In the middle Vth century the mosaics of the Baptistery of the Orthodox continued the tradition of Gala Placidia’s. This baptistery* consists of a lower part covered with stucco and a dome covered with mosaics. The topics represented in this cupola (dome) are divided into three zones. A circular zone at the top center, with the baptism of Christ, is surrounded by very hieratic images of the Apostles located between flowers and acanthus columns and under a cloth baldachin*. A lower decorated zone contains a design based on architectural representations that frame thrones and altars with sacred books as a remembrance of the architectural decorative paintings of Pompeii known as “Pompeian Styles” already discussed in a previous essay.
*Ambulatory: The ambulatory (Latin: ambulatorium, lit. “walking place”) is the covered passage around a cloister or the processional way around the east end of a cathedral or large church and behind the high altar.
*Baldachin: A baldachin, or baldaquin is a canopy of state typically placed over an altar or throne. It had its beginnings as a cloth canopy, but in other cases it is a sturdy, permanent architectural feature, particularly over high altars in cathedrals, where such a structure is then called a ciborium when it is sufficiently architectural in form. “Baldachin” was originally a luxurious type of cloth from Baghdad, from which name the word is derived. On time, the word for the cloth became the word for the ceremonial canopies made from the cloth.
*Baptistery: The part of the church as a separate centrally-planned structure surrounding the baptismal font where the baptism is practiced. The baptistery may be incorporated inside the church and can also be found as a chapel with its own altar.
*Lunette: A crescent-shaped (thus its name) or semicircular alcove containing a painting, a statue or totally empty.