Since ancient times, man has used mosaic as a technique of decorative art. Depending on the region and on the period, this art developed in different ways, adopting different techniques, materials, colors and esthetic patterns.
Starting from the simple arrangement of pebbles into a pattern by primitive man to indicate direction or convey a message, this technique has gradually developed and found new applications: from covering floors, to the decoration of villas and cathedrals, down to the modern expressions of mosaic art.
Despite many collocate the origin of the mosaic in Greece, around the V century BC, one of the most ancient examples of mosaic art is the white, red and black terracotta cone mosaic which was discovered in Uruk (Warka), dating back from the 3rd millennium BC.
Pre Columbian civilizations were also using colorful finely cut mosaic in the production of masks and other items. However, the origin and development of this decorative art is usually associated to the Mediterranean and Middle Eastern culture.
In general, three main phases can be determined in the development of mosaic art in antiquity.
The first involved the gradual perfecting of the pebble medium, particularly by Greeks in the 4th century BC. The second, which took place partly in the Hellenistic Greek world and partly on Roman soil, saw the invention and spreading of the tesserae technique. The third, largely a Roman phenomenon, was characterized by the popularization of mosaic and the application of the medium to new functions.
At the end of the 4th or the beginning of the 3rd century BC, the introduction of new principles led to the abandonment of the pebble technique. Artists began to use regular parallelepiped shapes, cut with stone material, producing opus tessellatum floors. Some scholars attribute this method to Morgantina (Sicily), others to Alexandria (Egypt). Cut mosaic pieces permitted the nearly complete elimination of the disturbing effects of visible mortar patches, and new materials, above all glass, offered a vast new range of colours. The following step in the improvement process of mosaic art was the impulse to create ever more complex representations. They were called opus vermiculatum and they were made of increasingly small tiles, down to 1mm, in size used to represent emblemata. An emblema is a picture that artists often conceived without knowing where it would be sent.
Eager to adopt the artistic culture of the Hellenized eastern Mediterranean, the Romans introduced mosaic in this exquisite form in both their domestic architecture and their places of worship. Amazing examples of this influence are the beautiful mosaics in Pompeii.
The Romans transformed mosaic from an exclusive art to a common decorative medium. They developed a simpler and less artistic kind of mosaic, probably stimulated by new and functional ways of thinking about the role of floors in architecture. To the practical Romans it may have seemed illogical that floors destined for rough wear should bear delicate pictures. Moreover, the demand for large-scale mosaic making brought about by the colossal urban expansion in the 1st century AD made the development of quicker and simpler techniques imperative.
Competition with painting in illusionistic and coloristic refinement was therefore abandoned; emblÄ“mata gave way to decorative elements distributed over the floor in one large overall pattern or to figure compositions taking the full floor plane; and polychrome gave way to monochrome mosaics (which may have been easier to produce).
In the provinces of the empire, local mosaic schools developed different specificities. In the Gallie, for example, mosaic with geometric motifs were the most common, while in the provinces of Africa figurative mosaics were more appreciated. The expressionist Roman style, which flourished in Italy, penetrated into the former Greek cities in the eastern part of the empire, but polychrome and types of composition based on the framed picture persisted with especial tenacity due to strong local Hellenistic traditions. Influence from these areas may have been responsible for the renewed opulence, represented by a vivid polychrome pictorial mosaic, which reappeared in Roman art in late antiquity.
In the course of the 3rd century the status of mosaic was radically altered. Mosaic gradually was introduced into new fields, like, for example, into garden architecture, bathhouse decoration, etc.. Very important is also the evidence that mosaic was used to depict sacred images that were put on walls.
Early Christian mosaics
Is during the early phase of Christianity that this new practice developed into a real art form. However, it seems certain that wall mosaics had come into use in Roman art well before Emperor Constantine’s edict of toleration of the Christian faith in ad 313. Christian art, afterward, assured the development of this decorative art, that until that moment was not as successful as the wall opus tessellatum.
Mosaic developed as an artistic tradition in the artistic and religious main centres: Rome, Milan, Ravenna and Constantinople. It is possible to detect two iconographic styles belonging to two different traditions: the former is characterised by a strong Roman style, the latter is a profound Byzantine style marked by transcendence, abstraction, sacredness and polychromy.
With the rise of the Byzantine empire, from the 5th century onwards, the art form gained new characteristics. These included eastern influences in style and the use of special glass tesserae (smalti). In the East, the circular church of Áyios Geórgios at Thessaloníki, Greece, shows Byzantine mosaic at its earliest flourishing (c. ad 400). Hallmark of Byzantine mosaic technique, is the profusion in the use of gold and silver and the combination of natural stone, with its gentle gradations, with the violent juxtapositions of coloured glass tesserae.
In the mosaics of the 6th century are found the earliest refinement introduced by the Byzantines to enhance the brilliance of gold tesserae. This refinement, already described, involved setting gold cubes at oblique angles to direct their reflections toward the viewer. Used in haloes, the tesserae, obliquely set, convey to the holy figures a miraculous aura of light. Splendid mosaics from many parts of the eastern Mediterranean testify to the continuous cultivation and improvement of these effects.
Apart from the gold ground, which had considerable impact, the technical subtleties essential to these mosaics met very little response outside Byzantium. When Byzantine artisans operated in foreign territory, they brought their particular techniques with them. Again and again the impact of this tradition was felt in the West, though, at its purest, mostly as short-lived episodes.
Mosaics made in Ravenna for the Ostrogoth king Theodoric (ad 493–526) are the first full manifestations of Byzantine art in the West. As seen in two of the foremost works from his time, the Baptistery of the Arians and the church of S. Apollinare Nuovo, the gold background now dominates. Accompanying it was silver, a novelty among the mosaics of Italy. In S. Apollinare Nuovo, the faces and hands in several of the Christ scenes are set not with glass tesserae but with cubes of stone. Stylistically, these mosaics are characterized by more static figures and less depth and plasticity than in those of the 5th century.
The tendency to depict icon-like, motionless mosaic figures isolated on a gold background became a leading decorative principle in the middle Byzantine age. Colour and technique show a continuation of the early Byzantine tradition, but preoccupation with light became stronger than ever and linearism (the expression of form in terms of line rather than colour and tone) took in these centuries a great step forward.
The 9th and 10th centuries are also characterised by the development of a close interrelation between architecture and mosaic. The earliest fully preserved examples of it are from the 11th to 12th. The 20th-century Austrian scholar Otto Demus, in his studies on the aesthetics of middle Byzantine mosaic art, has coined the term space icons for this kind of imagery, in which the forms of architecture collaborate to make the solemnly stylized figures appear with unexpected tactility.
In the following centuries we witness the appearance of a new style. The use of gold and silver is reduced, with the gradual toning down of the many splendid effects of the earlier tradition for the sake of the equilibrium and clarity of the whole. This drying out of the effects of light and colour was partly compensated for by a perfectionist setting and spacing of the tesserae.
In the late Byzantium age, the phenomenon called the Paleologian Renaissance (from the dynasty of the Palaeologians, 1261–1453) led to a renewal of Byzantine mosaic art. The stylistic change was clearly influenced by the vital humanism, which penetrated westward and laid the foundations for the Italian Renaissance. A peculiar vivacity invaded religious art, together with a sense of pathos and of the tragic. The results, as expressed in mosaics, were extraordinary. The tessera size became smaller than it had been in earlier epochs. Contours lost their rigidity, became thinner, and were occasionally abolished. Colour was somehow reintroduced with some interest for the effects of gold.
The prestige, both cultural and political, enjoyed by Byzantium in the Middles Ages led to a widespread imitation of its arts. Art objects in great number were imported to the West from Constantinople and other Greek centres. Individuals or communities outside the realm of Byzantium, however, were able to secure Byzantine artisans for the execution of monumental mosaics. Despite the Byzantine hegemony in the arts, in the early Middle Ages, Rome had been able to maintain and defend a mosaic tradition of its own.
With the downfall of Byzantium in the 15th century, there perished that milieu in which mosaic had been constantly cultivated and had undergone continuous renewal in response to changing patterns of religious and cultural life. The art lost another foothold in Italy at the beginning of the same century, when changing attitudes about the world and about the function of art eliminated the very bases upon which mosaic had been built.
Although mosaic continued to be used to a certain extent as church decoration, it was a changed art. Some of its traditional glitter was retained, but essentially mosaics became imitations of painting. The preparatory work was divorced from the execution: the artist submitted his cartoon and left its transposition into mosaic to artisans. This drew the lifeblood from the art and caused its degradation.