Alexander Mosaic in the context of "House of the Faun"

A Roman mosaic is a mosaic made during the Roman period, throughout the Roman Republic and later Empire. Mosaics were used in a variety of private and public buildings, on both floors and walls, though they competed with cheaper frescos for the latter. They were highly influenced by earlier and contemporary Hellenistic Greek mosaics, and often included famous figures from history and mythology, such as Alexander the Great in the Alexander Mosaic.

A large proportion of the surviving examples of wall mosaics come from Italian sites such as Pompeii and Herculaneum. Otherwise, floor mosaics are far more likely to have survived, with many coming from the fringes of the Roman Empire. The Bardo National Museum in Tunis has an especially large collection from large villas in modern Tunisia.

The Companions (Greek: ἑταῖροι, Greek: [heˈtairoi̯], hetairoi) were the elite heavy cavalry of the Macedonian army from the time of King Philip II of Macedon, achieving their greatest prestige under Alexander the Great, and regarded as the first or among the first shock cavalry used in Europe. Chosen Companions, or Hetairoi, formed the elite guard of the king (Somatophylakes).

Philoxenus of Eretria (Ancient Greek: Φιλόξενος ὁ Ἐρετριεύς) was a painter from Eretria. He was a disciple of Nicomachus of Thebes, whose speed in painting he imitated and even surpassed, having discovered new and rapid methods of coloring. According to Pliny, a picture of his was inferior to none, in particular his depiction of a battle between Alexander the Great and Darius III, which he painted for King Cassander.

A similar subject is represented in the celebrated Alexander Mosaic found in the House of the Faun in Pompeii. As a disciple of Nicomachus, who flourished about 360 BC, and as the painter of the battle of Issus (333 BC) (or possibly the battle of Gaugamela in 331 BC; Pliny simply states that it was "a picture representing one of the battles between Alexander and Darius"), Philoxenus must have flourished in the age of Alexander, from about 330 BC and onwards. The words of Pliny, "Cassandro regi", "Cassander being king", if taken literally, would mean that the creation of the original picture must have taken place some time after 317-315 BC, during the reign of Cassander in Macedon.