1. Hellenistic period

The production of Hellenistic mosaic floors in Pergamon is fortunately testified not only by the information provided by the archaeological remains themselves, but also by ancient literary sources. Pliny the Elder (23-79 AD) cites Pergamon as the place where Sosus, one of the very few known mosaicists of classical Antiquity¹ and the only one mentioned in an ancient text, was working. Modern studies suggest that Sosus’ period of activity is dated before 133 BC.²

According to Pliny, Sosus paved in Pergamon a mosaic called “asarotos oikos”, that is to say the mosaic representation of an unswept floor after a dinner, which renders the habit of the guests to throw the remains of the meal onto the floor. The original of Sosus, which was polychrome according to Pliny’s description, is lost. Some Roman copies, however, are preserved. The best one, produced in opus tessellatum, is in the Museo Gregoriano Profano of the Vatican. This bears the signature of the artist Heraclitus, “ΗΡΑΚΛΙΤΟΣ ΗΡΓΑΣΑΤΟ”, thus revealing the name of a mosaicist of a later date, perhaps of the 2nd cent. AD. In this copy, chicken bones, seashells, fish bones, lobster’s pincers, sea urchins, fruits etc are depicted, scattered on the surface. The realism of the morphology of the objects (but not their proportions), the consistency in shading, the similarity of the theme (e.g. the unswept floor) and the spatial setting of the mosaic, contribute to the creation of a scene with optical illusion effects (trompe l'œil). Moreover, the depiction of a mouse enriches the scene with a narrative element, enhances its realistic character and functions as a surprising, “scary” detail, which gives a playful tone to the representation.

After the reference to the “asarotos oikos”, Pliny describes the mosaic with the depiction of doves standing on the rim of a cup.³ This mosaic has been extensively copied, but the best known copy was found in Hadrian’s villa in Tivoli and it is exhibited in the Musei Capitolini in Rome. The vividly coloured tesserae depict naturalistically the morphological and chromatic features of the birds, the reflections on the glossy surface of the metal vessel and the undulation of the water, where the doves drink. Even though Pliny’s text does not clarify whether the "doves mosaic" was part of the “asarotos oikos” mosaic, it is certain that it was also in Pergamon.⁴

The most significant Hellenistic mosaics in Pergamon, which have been found in situ, decorated the complex of the Attalid Palaces in the NE side of the acropolis and, most specifically Palace IV and Palace V. The best-known examples are those of Palace V, which are dated to the first half of the 2nd cent. BC. They adorned the “Altar Room” and the “Northwest Room”. The composition of the first floor is recorded in the excavators’ drawings. However, immediately after they had unearthed it, the mosaic was severely damaged. The design included five emblemata in rectangular frames, from which only three survived in a fragmentary state: two theatrical masks –a tragedy mask and a comedy mask-and a parrot. The parrot is executed in opus vermiculatum and the precision in the rendering of its morphology made possible its identification with the species “psittacus torquatus”.⁵ The decoration of the floor is complemented with bands of repetitive motifs in various colours (e.g. astragal, lozenges), rosettes, fruit garlands and small birds in opus tessellatum. The mosaic floor of the “Northwest Room” is destroyed in the centre and is surrounded by successive ornamental bands. Among these bands, a small scroll with the signature of the mosaicist Hephaistion (“ΗΦΑΙΣΤΙΩΝ ΕΠΟΙΕΙ”) is depicted, fixed on its corners with pieces of red wax. One of its corners has been removed, casting a shade on the surface where it was fixed. The particular rendering of the scroll is indicative of the naturalistic style and the quality of the Pergamon mosaics.

Conclusively, it could be said that the Hellenistic mosaics in Pergamon were produced by employing the technique of opus tessellatum, and more specifically of opus vermiculatum. They were of outstanding quality, obviously imitating works of painting, while the emphasis is on the realistic, detailed representation of the figurative themes. As a result, certain mosaics became ideals which were imitated for a long period of time after their first production in a wide geographical area. This fact reveals that there were artists or groups who travelled and produced mosaics, as well as the prompt imitation among the artists. In addition, the Hellenistic mosaics were very popular and thus extensively copied in Roman times, in a way similar to painting.

2. Roman period

The transition from the Hellenistic to the Roman period is characterized by an almost incessant economic growth of the cities of Asia Minor. In Pergamon in particular, more than in any other city in Asia Minor, the development of the mosaic production was rather continuous. The establishment of the Roman Province of Asia in 129 BC signals the transition from Hellenistic to Roman mosaics. Some mosaic floors in opus tessellatum with geometric or floral designs of typical Hellenistic patterns such as guilloches, wavebands, patterns of squares, lozenges, meanders, cubes belong to this transitional phase. The rendering of some motifs in perspective, for instance the meanders and the cubes, continues the Hellenistic tradition of the optical illusion.

At the same time, some elements of Italian influence occur in this period, such as black and white patterns or pictures in the centre of the floor laid in the opus sectile technique. Gradually, the Italian influences become more explicit, although the reminiscences of the Hellenistic production do not disappear. A typical example of the second group is the floor mosaic of a hall to the north of the peristyle of the court of “Building Z”. The centre of the floor is occupied by the representation of a Silen and a young Dionysus, who are portrayed from the chest upwards, which is unusual. The central panel is framed by patterns of cubes and meanders in perspective, outlined by successive bands of repetitive motifs (waveband, squares, monochrome bands). Masks fill the corners of one of the borders which frame the central panel. The mosaic reflects the Hellenistic compositions of Delos, not only due to the pictorial theme (Dionysus, Silen, masks), but also due to the coherence and the representation of the motifs.⁶

On the contrary, in another room of the same building, to the west of the peristyle, the intrusion of Italian elements becomes more evident. The pictorial decoration of the floor consists of sixteen octagons which are framed by guilloches and are adorned with designs connected to Dionysus (theatrical masks, tiger, panther, satyr, maenad, cock) on a dark ground. The three-dimensional representation of the figures is a Hellenistic feature. Nevertheless, the octagonal borders, the extensive use of the guilloche and the strict geometric patterns which fill the outer parts of the floor are features of the Roman period.