The Mosaics of Ravenna

The mosaics of Ravenna cannot be understood without the strange destiny of the city. A small lagoon town sheltered by marshes, Ravenna was, within a century and a half, the capital of three successive powers — and each left its gold there.

From Honorius to the Exarchate: why Ravenna?

In 402, Emperor Honorius, threatened by the invasions, transferred the Western imperial court from Milan to Ravenna, better defended by its waters. The city thus became the last capital of the Western Roman Empire^[2]. After the fall of Rome (476), it remained the seat of power: first that of Odoacer, then above all that of Theodoric the Great, king of the Ostrogoths, who seized it in 493 and reigned there until 526^[3]. Finally, under Emperor Justinian, the general Belisarius retook the city in 540; Ravenna became the capital of the Byzantine Exarchate in Italy, until the Lombard conquest of 751^[4].

Three centuries, three masters, a single passion: to build and to decorate. Each power wanted to engrave its faith and its glory in the gold of the apses. That is why Ravenna offers, within a few hundred metres, a unique shortcut through the history of Christian art — from the waning Roman 5th century to full Byzantine flowering.

Two Christianities face to face: Catholics and Arians

This setting conceals a spiritual drama that explains half the images of Ravenna. Theodoric and his Gothic people were Christians, but Arians: they held the Son to be a creature subordinate to the Father, and not God of the same nature — against the faith defined at Nicaea (325)^[5]. The Roman population of Italy, on the other hand, was Catholic ("orthodox", that is, Nicene). For two generations, then, Ravenna lived with two parallel Churches, two clergies, two baptisteries and two cathedrals — one Arian, the other Catholic.

After the Byzantine reconquest, the Arian buildings were reconciled to Catholic worship. Theodoric's palatine church, Sant'Apollinare Nuovo, was reconsecrated to the Catholic rite in 561 under Bishop Agnellus^[6]. This history is no scholarly detail: it left visible traces in the mosaic itself, down to ghostly hands forgotten on columns (see below). At Ravenna, the battle for the divinity of Christ can be read on the walls.

Why mosaic, and why gold?

Before reading the images, the material must be understood. A wall mosaic is not a fresco: it is made of tesserae, small cubes assembled one by one in a bed of mortar. At Ravenna these are mostly smalti: glass made opaque and coloured through, of a solidity and brilliance painting never knows^[7]. The golden grounds are achieved by a feat: a thin leaf of gold is imprisoned between a thick glass backing plate and a fine protective film of glass (the cartellina)^[8].

Above all, the Ravennate mosaicists laid their tesserae not flat, but slightly tilted, each at a slightly different angle. The result is that no surface is ever uniform: depending on where you stand, on whether you advance or pray, the gold catches the light and returns it in waves. In the half-dark of a church, by the trembling light of candles, the wall seems alive^[9]. This quality is no gratuitous decorative effect: it makes mosaic the liturgical art par excellence, an art that truly exists only in the light of worship.

This is where Ravenna's uniqueness is decided, and the particular angle of this article. These mosaics are not pictures that happen to hang in a church: they are the church, its inner skin, the heaven beneath which the mystery is celebrated. To read them, they must be looked at from the Mass.

Gold, or the light of heaven

Why all this gold? Because gold imitates nothing earthly. It is neither a landscape, nor a natural sky, nor a wall: it is a light. In the Byzantine tradition, the gold ground signifies the world of God, the divine light and the shadowless place of eternity^[10]. By tearing figures away from all realistic scenery to set them upon gold, the mosaicist places them outside time, in heaven: Christ, the Virgin, the saints are no longer in an episode, they are in glory. The believer who enters raises his eyes and finds himself, literally, surrounded by heaven.

This intuition echoes the great Johannine description of the heavenly Jerusalem:

"The city was pure gold, clear as glass. […] And the city has no need of sun or moon to shine upon it, for the glory of God is its light, and its lamp is the Lamb." — Revelation 21:18, 23^[11]

The golden walls of Ravenna are an attempt, in glass and fire, to make visible that unwaning light — the city where "night shall be no more" (Rev 22:5).

Images that come alive in candlelight

Because they are made of tilted glass, these images never yield themselves up at once. They change as you move, they shine when candles are lit, they fall silent in full daylight and wake in the liturgical half-dark. In other words, the mosaic needs worship in order to live: it is in procession, incense and candles that it reveals its depth. Here art meets its end. As the Second Vatican Council would later recall, sacred art has meaning only when oriented toward God:

"The fine arts are rightly classed among the noblest activities of man's genius, and this applies especially to religious art and to its highest achievement, which is sacred art. These, by their very nature, are oriented toward the infinite beauty of God which they attempt in some way to portray by the work of human hands." — Second Vatican Council, Sacrosanctum Concilium, § 122^[12]

Seeing the faith: the image and the Word

Why did the Church want, from antiquity onward, to cover her walls with images rather than leave them bare? The answer is ancient and has never varied: because the image teaches, and because the Word became flesh. The invisible God cannot be painted; but the Son who made himself visible can. The Catechism of the Catholic Church puts it plainly:

"The sacred image, the liturgical icon, principally represents Christ. It cannot represent the invisible and incomprehensible God, but the Incarnation of the Son of God has ushered in a new 'economy' of images." — Catechism of the Catholic Church, § 1159^[13]

And the Catechism at once quotes Saint John Damascene, the great defender of images in the 8th century:

"Of old, God the incorporeal and uncircumscribed was never depicted. Now, however, when God is seen in the flesh, and dwells among men, I make an image of the God whom I see." — Saint John Damascene, quoted by the Catechism, § 1159^[14]

The Second Council of Nicaea (787), which closed the iconoclast controversy, went so far as to name Ravenna's technique expressly:

"Like the precious and life-giving Cross, the venerable and holy images — painted or made of mosaic or of any other suitable material — are to be exhibited in the holy churches of God." — Second Council of Nicaea (787), quoted by the Catechism, § 1161^{[15] [16]}

That the council should mention, alongside painting, mosaic, is no accident: it had before its eyes the monumental art of the great churches of the East and of Ravenna. Image and word, the Catechism adds, "illuminate each other"^[17]. The mosaics of Ravenna are exactly that: the Gospel written in light for a people who, for the most part, could not read. On this doctrinal foundation — why the Church depicts God — see Why does the Church use images? and The difference between icon, idol and sacred image.

The oldest and most moving of the Ravennate ensembles is also the smallest: a modest brick building in the shape of a cross, raised around 425–450 and linked to the name of Galla Placidia, daughter of Emperor Theodosius and regent of the Western Empire^[18]. Tradition makes it her mausoleum, though she was almost certainly never buried there — she died in Rome in 450^[19]. No matter: inside, the visitor receives one of the most powerful shocks in all Christian art.

The central vault is a night sky: a deep blue sown with golden stars turning in concentric circles around a golden cross at the summit. You do not raise your eyes to a ceiling: you raise them to the firmament, and at the heart of the firmament reigns the Cross. All around, in the lunettes, stags drink at the spring — image of the Psalm "as the thirsty stag longs for running water" (Ps 42) — doves drink from basins, and two scenes dominate.

The first shows Christ the Good Shepherd: no longer the little rustic shepherd of the catacombs, but a majestic young Christ, clad in gold and purple, seated among his sheep, his hand resting on one of them, a long cross for a crook^[20]. The second evokes the martyrdom of Saint Lawrence, advancing toward the burning gridiron, the cross on his shoulder, beside an open cupboard displaying the Gospels. Thus, already in the 5th century, the programme is liturgical and paschal: the Cross at the centre of heaven, the Shepherd who gathers, the martyr who follows the Lamb, and the starry heaven promised to all. On the long history of these first images, see Early Christian art and The Christian symbols of the catacombs.

Baptism is the gateway to the whole liturgical life. It is no surprise that Ravenna left us two baptisteries wholly decorated — one Catholic, the other Arian — and that both place the same scene at the crown of their dome: the Baptism of Christ.

The Neonian Baptistery (of the Orthodox)

The older one, called Neonian (after Bishop Neon, who commissioned its decoration around 458) or "of the Orthodox", is an octagon raised over former baths^[21]. At the centre of the dome, in a medallion, Christ stands naked in the waters of the Jordan, receiving baptism from John the Baptist, while the dove of the Spirit descends and a bearded old man, the personification of the River Jordan, attends the scene^[22].

Around this medallion, the twelve apostles advance in procession, led by Peter and Paul, each bearing a veiled crown — the crown of the elect which they present to God. The baptized who went down into the font, at the centre of the building, raised his eyes and saw himself promised to that company: plunged into the death and resurrection of Christ, he entered the ring of the saints. The very geometry of the place — the octagon, eight sides — spoke of the "eighth day", the endless day of the Resurrection. This language of number and space is also found in The symbolism of the altar.

The Arian Baptistery

A few streets away, Theodoric had raised around 500 the baptistery of his own community, called of the Arians^[23]. The scene is the same — Baptism of Christ, John the Baptist, the dove, the personified Jordan — and the twelve apostles process there too. But one difference can be read by those who know how to look: they advance toward an empty throne surmounted by a cross, the hetoimasia, "the prepared throne" for Christ's return^[24]. Historians readily stress the Arian insistence on the humanity and body of Christ. Yet the decoration remains so close to that of the Catholics that one measures, here, how much liturgy united in gesture those whom dogma divided — and how much these places afterwards needed to be reconciled to the full faith of Nicaea.

Close by, the small Archiepiscopal Chapel (the private oratory of the Catholic bishops, around 495–500) answers Arianism with an image of combat: Christ in warrior's dress (Christus militans), trampling the lion and the serpent, the cross on his shoulder and the open Gospel with these words — "I am the way, and the truth, and the life"^[25]. Against those who lowered the Son, Catholic Ravenna retaliates by showing Christ victorious and Lord.

No church in Ravenna says the bond between image and liturgy better than Sant'Apollinare Nuovo. Theodoric had it built and dedicated around 504 as an Arian palatine chapel, adjoining his palace. Reconciled to Catholic worship in 561, it keeps, on the two long walls of the nave, one of the most striking programmes in all Christian antiquity^[26].

The oldest Gospel cycle

High up, beneath the ceiling, runs a band of twenty-six small scenes: it is, preserved in situ, the oldest New Testament cycle in mosaic to have come down to us — the miracles and parables of Christ on one side, his Passion on the other^[27]. Remarkably, in the Passion scenes Christ is still shown beardless, young and serene: art had not yet fixed the face we know. We stand at the very origins of Christian iconography, before the type of Christ Pantocrator imposed itself in the East.

Virgins and martyrs in procession

But it is the two great lower registers that strike the believer. On the left wall, setting out from the port of Classe depicted with its ships, twenty-two holy virgins advance in file, led by the three Magi, toward the Virgin and Child enthroned between four angels. On the right wall, setting out from Theodoric's Palace, twenty-six martyrs process, led by Saint Martin, toward Christ in majesty^[28]. These two registers belong to the Catholic phase of the church: executed after the reconciliation of 561, they cover the original Arian decoration. A precious detail: the Magi are named Balthazar, Melchior and Gaspar — the oldest known mention of these three names in Christian art^[29].

Yet these processions are no mere decoration. They double, on the walls, the real procession of the faithful advancing down the nave toward the altar. The people of God climbing toward the altar walk, right and left, escorted by the people of the saints climbing toward Christ and toward the Virgin. The earthly assembly and the heavenly assembly form a single movement. Each saint, moreover, is named (a titulus surmounts him): the liturgy does not invoke an anonymous crowd, but friends of God who can be called by name. It is, in mosaic, the communion of saints.

The erased memory: the Arian figures of the Palatium

This wall keeps a scar. Originally, between the columns of Theodoric's Palace, stood figures of the Arian court. After the Catholic reconciliation, they were erased: the figures were replaced by curtains. But the 6th-century mosaicists worked too fast or too scrupulously: on some columns, disembodied hands still survive, forgotten against the gold ground, mute witnesses of a damnatio memoriae^[30]. These ghostly hands are among history's most moving documents: the trace, in gold, of the day Ravenna returned to the full faith of the Incarnation.

With the basilica of San Vitale, consecrated in 547/548 by Bishop Maximian and financed by the immensely rich banker Julianus Argentarius — who sank, it is said, twenty-six thousand gold pieces into it^[31] — we reach the summit. Here the decoration no longer merely illustrates the Gospel: it comments on the Mass celebrated beneath it. The whole octagon, its green vaults, its gold and paradisal greens, converge on the choir and the altar.

Christ upon the globe of the world

In the conch of the apse, the young, beardless Christ, clad in purple, sits not on a throne but upon the blue globe of the cosmos: he is the Master of the universe. With his right hand he holds out the crown of martyrdom to Saint Vitalis, the patron of the church; on the left, Bishop Ecclesius offers him the model of the basilica^[32]. Beneath his feet flow the four rivers of Paradise. Christ reigns over the world, but it is toward the altar placed just below that the whole programme leads the gaze.

Abel, Abraham, Melchizedek: the altar and the Roman Canon

Here is the liturgical heart of Ravenna, and the deepest point of the whole building. On either side of the choir, right beside the altar, two great lunettes show three sacrifices of the Old Testament: Abel offering his lamb, Melchizedek presenting bread at an altar where the chalice already stands, and the offering of Abraham (the hospitality to the three angels and the sacrifice of Isaac)^[33]. Why these three, precisely, around the altar?

Because they are exactly the three sacrifices named by the Canon of the Mass. In the great Roman Eucharistic prayer, after the consecration, the priest asks God to look upon the offering as he once accepted those of the just:

"Be pleased to look upon these offerings with a serene and kindly countenance, and to accept them, as once you were pleased to accept the gifts of your servant Abel the just, the sacrifice of Abraham, our father in faith, and the offering of your high priest Melchizedek, a holy sacrifice, a spotless victim." — Roman Canon of the Mass, the prayer Supra quae^[34]

The mosaicists of San Vitale thus made the walls of the choir the visual gloss on the Canon. While the priest pronounces the names of Abel, Abraham and Melchizedek, the believer sees them offering, at altar height, their sacrifices which announced Christ's. The bread of Melchizedek (Gen 14:18), the lamb of Abel, the only son of Abraham: the whole expectation of the Old Covenant converges upon the one sacrifice now offered on this altar. Eucharistic typology, elsewhere reserved to books, is here built into stone, exactly where the Mass makes it present. This language of altar and offering is explored further in The symbolism of the altar.

Justinian and Theodora: the imperial offering

There remains the most famous image of Ravenna. On the two walls of the choir face each other two court processions. On the left, Emperor Justinian, his brow ringed with gold and his shoulders in purple, surrounded by his soldiers, his clerics and Bishop Maximian — the only figure named by an inscription — bears in his hands a golden paten, the plate of the Eucharistic bread^[35]. On the right, Empress Theodora, adorned with jewels, presents the chalice^[36].

The emperor brings the bread, the empress brings the wine: they advance toward the altar at the offertory, when the people present their gifts for the celebration^[37]. These are not commemorative portraits hung on a wall: they are an offering made eternal. So long as Mass is celebrated at San Vitale, Justinian and Theodora will bear the bread and wine there, fixed in the liturgical gesture par excellence. It should be noted, to remain exact, that the sovereigns' golden halo marks here their quasi-sacred dignity as Christian emperors, and not a canonization^[38]. But the message is clear: before the altar, the highest power in the world is but a servant bearing the offering.

A few kilometres away, in the former port of Classe, the great basilica of Sant'Apollinare in Classe, consecrated in 549 by Maximian, keeps one of the most theologically dense apses in all Christian art^[39]. In a single glance can be read the liturgy as transfiguration.

The jewelled cross and the face of Christ

At the crown of the apse, upon a great blue disc sown with stars, shines an immense jewelled cross (the crux gemmata, a cross adorned with precious stones). At its centre, tiny and luminous, the face of Christ. Above, emerging from the clouds, the hand of God the Father; on either side, in bust among the clouds, Moses and Elijah^[40]. The scene is clear: it is the Transfiguration of Tabor (Mt 17), where Christ appeared radiant with light between Moses and Elijah while the Father's voice resounded. But here, the transfigured Christ has become the glorious Cross — for it is through the Cross that true glory passes.

"And he was transfigured before them, and his face shone like the sun, and his garments became white as light. And behold, there appeared to them Moses and Elijah, talking with him." — Gospel according to Saint Matthew 17:2-3^[41]

Three sheep raise their heads toward the cross: they are the three apostles who witnessed Tabor, Peter, James and John^[42]. At the foot of the cross, the inscription proclaims the meaning of everything: SALVS MVNDI, "the salvation of the world"^[43].

Saint Apollinaris in prayer: the bishop who intercedes

Beneath this transfigured heaven stretches a green paradise — rocks, trees, birds — and in its midst stands, alone, Saint Apollinaris, first bishop of Ravenna, vested in the garments of the Mass (the white alb, the chasuble, the pallium). He is shown in prayer: arms raised and open, in the ancient gesture of liturgical prayer. Around him, twelve sheep: his people, the faithful entrusted to his keeping^[44].

This gesture of outstretched arms is no decoration: it is precisely the attitude of the priest who, at the altar, calls down the Spirit upon the people and upon the offerings^[45]. The bishop of Classe is thus figured in the very act of his ministry: standing between heaven and his flock, he intercedes, and it is through his prayer that the sheep are led upward toward the glory on high. The whole apse sets before the eyes what the Mass accomplishes: beneath the Transfiguration of Christ, the shepherd prays, and the people are transfigured as they ascend toward the light. The image does not stand beside the liturgy — it is the liturgy made visible.

Fifteen centuries later, these walls continue to do what they were designed for: not to decorate, but to uplift. They teach first a lesson in theology: heaven is shown only by transfiguring matter. Glass, gold, stone — the humblest matter — become, in the artist's hand and at the service of worship, the place where the light of God passes. That is exactly what the Catechism says of sacred art:

"Sacred art is true and beautiful when its form corresponds to its particular vocation: evoking and glorifying, in faith and adoration, the transcendent mystery of God, the surpassing invisible beauty of truth and love visible in Christ." — Catechism of the Catholic Church, § 2502^[46]

They then teach a way. Before the gold of San Vitale or the starry cross of Classe, the most indifferent visitor feels something rise within him: it is the via pulchritudinis, the way of beauty, by which the soul senses God before it even reasons about him. John Paul II said it to the artists of the whole world:

"Beauty is the key to the mystery and a call to transcendence. It is an invitation to savour life and to dream of the future." — Saint John Paul II, Letter to Artists (1999), § 16^[47]

That is why Ravenna remains, today still, a living catechesis. The tourist enters out of curiosity; he often leaves troubled, as if touched by a presence. The mosaicists of the 5th and 6th centuries did not seek to make their art admired: they sought to open a window onto heaven, above an altar, so that the praying people might glimpse, beneath gold and glass, "the Lord God [who] will be their light" (Rev 22:5). On this underlying question — can beauty lead to salvation? — continue with Will beauty save the world?.

• The mosaics of Hagia Sophia — the other great home of mosaic, at Constantinople
• Christ Pantocrator — the type of Christ's face that would prevail after Ravenna
• Early Christian art — the origins of Christian art, from the catacombs to the basilicas
• The Christian symbols of the catacombs — the Good Shepherd, the orant, the fish
• The symbolism of the altar — the centre toward which all the decoration converges
• Why does the Church use images? — the doctrinal foundation of sacred images
• The difference between icon, idol and sacred image — the decisive boundary
• Will beauty save the world? — the way of beauty toward God