Mausoleum of Constantina


The Mausoleum of Constantina, also known as the Mausoleum of Santa Costanza, was built in the 4th century AD for Constantina, the daughter of the emperor Constantine I. It later became a church. It is located in Rome on the Via Nomentana, within the monumental complex of Sant'Agnese fuori le mura.
It is one of the best preserved buildings from Late Antiquity left in Rome and includes original ceiling mosaics. It was adjacent to the earlier basilica, now in ruins, built by Constantine I from 338 as a funerary hall. It was also built over part of the earlier Catacombs of Saint Agnes in which the martyr Saint Agnes is believed to be buried and over whose tomb was a small chapel nearby.
According to the traditional view, the mausoleum was built in the reign of Constantine I for his daughter Constantina, later also known as Constantia or Costanza, who died in 354. Ultimately, Constantina's sarcophagus was housed here, but it may have been moved from an earlier location.
The mausoleum is of circular plan with an ambulatory surrounding a central dome and survives in essentially its original form. Despite the loss of the coloured stone veneers of the walls, some damage to the mosaics and incorrect restoration, the building stands in excellent condition as a prime example of Early Christian art and architecture. The vaults of the apses and ambulatory display well preserved examples of Late Roman mosaics. A key component which is missing from the decorative scheme is the mosaic of the central dome. In the sixteenth century, watercolours were made of this central dome so the pictorial scheme can be hypothetically reconstructed. The large porphyry sarcophagus of either Constantina or her sister Helena has survived intact, and is now in the Vatican Museum – an object of great significance to the study of the art of Late Antiquity.

Location

Santa Costanza is located a minute's walk to the side of the Via Nomentana, the road that follows the ancient Roman route running north-east from Rome to Nomentum or Mentana. It lay a short way outside the ancient walls of Rome in a cemetery area, and probably in an Imperial family estate. The underground catacombs had been built there many years earlier and contained the relics of Saint Agnes who was martyred as a thirteen-year-old, and over whose tomb was a small chapel.

History

The funerary hall or "Constantinian basilica" was built first from 338 as a result of Constantina's devotion to Saint Agnes, a legend later considerably elaborated, but early Christians believed that their souls benefited from being buried close to martyrs, which was almost certainly a major attraction of the funerary hall to those who paid to be buried in it.
The mausoleum was built around 350, as shown by excavations in 1992 which discovered an earlier building beneath which may have been the baptistry built by Constantine, in which Constantina and her paternal aunt were baptised by Pope Silvester I, as recorded in Liber Pontificalis.
Annexing an important mausoleum to a basilica was a common practice at the time, as seen in the Mausoleum of Helena attached to the basilica of Santi Marcellino e Pietro ad Duas Lauros on Via Labicana. Other basilicas with floorplans typical of the Constantine era are San Sebastiano fuori le mura on Via Appia, San Lorenzo fuori le mura on Via Tiburtina and the anonymous basilicas on Via Prenestina and Via Ardeatina, the latter recently discovered and attributed as the burial place of Pope Mark.
The bodies of the sisters were both brought considerable distances to be buried there: Ammianus records that Constantina's body was brought back from Bithynia, and Helena's from Gaul.
The Constantinian basilica gradually fell out of use and into ruins, with the base of the wall now surviving for about a third of the original circuit of exterior walls, but Santa Costanza has survived all but intact. It is documented that Pope Nicholas I celebrated mass there in 865, the first time that "Santa Costanza" is recorded as its name, but its consecration as a church was not until 1254, by Pope Alexander IV, who had what were believed to be the remains of Constantia removed from the larger sarcophagus and placed under a central altar.

Architecture

Purpose

The structure of Santa Costanza reflects its original function as the mausoleum of one or both Constantine's two daughters, Constantia and Helena, rather than as the church it became much later. The centralized design put "direct physical emphasis on the person or place to be honored" and was popular for mausoleums and places of baptisms at this time. Other early Christian buildings with a similar origin and a circular plan include Split Cathedral, built within Diocletian's Palace as his mausoleum, and the Rotunda of Galerius in Thessaloniki built as a mausoleum for Galerius.

Structure

Santa Costanza is a circular, centralized structure, with a circular ambulatory ringing a high central space topped by a shallow dome, which is raised on a round drum, as can be seen from the exterior. It is built of brick-faced concrete and its structure is basically two rings supported by columns placed around a vertical central axis. The upper ring sits on the columns while the "lower ring encloses a circular ambulatory whose space flows between the columns into the axial cylinder." This design essentially creates two spaces or two worlds, that of the ambulatory and that of the upper dome. The screens of the ambulatory and inner ring create a dark contrast to the bright upper space of the dome. This contrast of light can be seen in the picture of the main interior. The single door, flanked by two arched niches, would originally have been an internal arch or doorway leading straight into the Constaninian basilica or funerary hall, half-way along its length. There is a short vestibule inside the door, opening to the ambulatory.
An arched arcade with twelve pairs of granite columns decorated with composite capitals supports the drum below the dome, and separates the area of the ambulatory beyond, which is much darker, as light from twelve windows in the clerestory does not reach this area as well. In contrast, the central area is well-lit, creating interplay between dark and light in the interior.
The number of arches, pairs of columns and windows could be a reference to the Twelve Apostles. Opposite the entrance in this central space there is "a kind of baldacchino...rises above a porphyry plaque which, below the middle arch of the center room, once seems to have carried the princess's sarcophagus". This is where the sarcophagus of Constantina, or perhaps the second one, would have rested. The ambulatory is barrel-vaulted and is 22.5 meters or 74 feet in diameter. The ambulatory has most of the surviving mosaics in the church. Larger arches mark the cardinal points in the mausoleum. The walls were probably covered in slabs of colourful marble, as was usual in imperial buildings. Santa Costanza was also to some extent a new type of building. It was different from earlier styles in that the roof, which would previously have been typically flat and made with wood, was instead designed as a dome and vault.

Decoration

Mosaics

The mosaics of Santa Costanza are important examples of Early Christian art, and even rarer examples of secular palace ceiling mosaics. The apses, central dome, and ambulatory all had mosaic decoration, though that in the dome no longer survives.
As evidenced by surviving Renaissance-era illustrations the church was likely once covered with mosaic decoration but today all that remains are those in the two apses and those in the ring barrel vault. In particular, the ring vault mosaics are well preserved and consist of eleven divisions of ornamental motifs, some of which are repeated. The mosaics here were composed using pieces of marble unlike the composition using glass cubes that would become popular in later works. The use of color is significant as the mosaics encompass a narrow range of colors including dark green, brown, red and yellow on a relatively plain light backdrop. This color scheme is comparable to earlier Roman mosaic compositions of the first half of the fourth century and dates these compositions to very soon after the completion of the structure as opposed to being later additions.

Mosaics in the apses

In the ambulatory wall there are two shallow apses, each with a mosaic showing Christ as the Pantocrator, the earliest surviving examples of this depiction; they probably date to the 5th or 7th century, though there has been much discussion of this. Like many mosaics of the period, both have suffered from restoration and both show elements of Roman imperial imagery, representing early examples of the conflation of this with Christian art. A mosaic with two women wearing white, reported as being behind the sarcophagus in the Renaissance, has now gone and was never drawn.
One of the apses shows a traditio legis: Christ is shown with Saints Peter and Paul giving Peter the scroll representing law, with the inscription, "DOMINUS PACEM DAT," or "The Lord is giving Peace." A few sheep represent his role as shepherd governing and leading his flock. Christ is clothed in golden robes, suggesting his power and supremacy. He is shown rising above paradise, which further shows his dominance over both heaven and earth.
In the second apse, Christ appears somewhat more simply but still as supremely powerful. His robes are not quite as rich as in the other apse, but still suggest power. He wears a simple tunic but it is purple and gold. This suggests not only holy power, but human power given that purple is the color of royalty and the gold stripes suggestion a connection to the Roman emperors. Peter also approaches Christ in supplication, like one would approach the Emperor. This is one of the first examples in Christian art of Christ being portrayed in the same way as the emperor or royalty. It is a concept that would later be prevalent in Christian art and architecture. In this apse Christ is not just portrayed as royalty but as the ruler of the world, of all existence. He sits atop a blue sphere, a clear symbol for the world or universe. From this perch he hands keys to Peter. This is a clear sign of Christ, and the power of heaven, giving authority and holy power to man. It is also important to note that Peter was Rome's first bishop so this meant Roman authority was sanctioned by God. This concept and picture of Christ as the almighty ruler and creator of the world would be the norm in the artwork of later churches, but it first appears here at Santa Costanza.