Between the ruins of ancient Ostia we still find many beautiful mosaics. In a previous post I already discussed the mosaics in the mithraeum of Felicissimus, which are not just impressive, but also provide us with a lot of information about the mystery cult of Mithras. Ostia’s many complexes of public baths also have several mosaics which are certainly worth a visit. In this post I want to take a closer look at some of my personal favourites. I will start with a mosaic from the so-called baths of the provinces. This complex dates from the days of the emperor Nero (54-68). His predecessor, the emperor Claudius (41-54), had created a new port north of Ostia which was called Portus. Unlike Ostia, it had the facilities to allow large grain ships to dock safely between the piers that were hundreds of meters long. Later the port of Portus was further expanded by the emperor Trajanus (98-117).
The complex from Nero’s time has unfortunately not been preserved. Already during the reign of the emperor Domitianus (81-96) this part of Ostia was thoroughly rebuilt and the ground level was raised by circa one metre. This explains why we can only admire part of the mosaic: its edges are hidden beneath the ground. The mosaic features shields, spears and geometric patterns. In the centre four dolphins seem to be having fun, while the four figures above and below refer to the four winds and four Roman provinces. These provinces are Africa, Egypt, Sicily and Spain respectively. The first three provinces were seen as the breadbasket of the Roman Empire. Before Claudius built his new port, grain ships from these provinces were often forced to dock at Puteoli in Campania, which had a much better harbour than Ostia. In Puteoli, the grain was transferred into smaller ships and then taken on to Ostia. It should be noted that the construction of Portus did not immediately put an end to this practice. At the start of the year 61, Saint Paul the Apostle travelled to Italy on a ship from Alexandria in Egypt. The crew dropped him off at Puteoli and the apostle had to walk to Rome from there (Acts 28:13-14). We can unfortunately only guess why the captain did not sail on to Portus.
The next mosaic is located in the vestibule of the House of the Fishes. A green fish can be seen swimming inside a white chalice, and next to the chalice there are two more red fish. The mosaic, which dates from the third century, is sometimes identified as a specifically Christian work of art. After all, the Greek word for fish is ΙΧΘΥC (ichthus), which also happens to be an abbreviation of Ἰησοῦς Χριστός, Θεοῦ Υἱός, Σωτήρ, meaning “Jesus Christ, Son of God, the Saviour”. The Christian interpretation of the mosaic is certainly not irrational, but at the same time it cannot be proven, in part because the image of the fish does not feature any (religious) texts. I must say I have certainly seen more convincing examples of Christian mosaics, for instance in a house in Kourion on Cyprus.
We now follow the decumanus maximus, the street running through Ostia from east to west. At the Porta Marina we then find a bar (caupona) from the third century. It has a nice floor mosaic which is unfortunately only partially visible from the street. The mosaic features two martial artists. The men are not boxers, but fighters who practice pankration. This was a martial art which basically allowed anything, except biting and gouging out the eyes of your opponent. Punching, kicking, grappling, choking and other forms of attack were, on the other hand, all part of the game. The names of the martial artists have been included in the mosaic: Alexander and Helix. It is quite possible that the two were real-life professional fighters in the first half of the third century.
Opposite the bar of Alexander and Helix stood the so-called House of the Nymphaeum. The house does not have a classical mosaic floor, but it does have a high-quality floor executed in opus sectile. Opus sectile involves cutting pieces of marble down to size and then assembling them to create a picture. Inside the house we see, among other things, Solomon’s knots.
Even more impressive is the House of the Dioscuri behind the House of the Nymphaeum. The Dioscuri are the twin brothers Castor and Pollux. In Rome the brothers shared an important temple on the Forum Romanum. The temple had been built after Castor and Pollux had supposedly aided the Romans in defeating the Latin League at the battle of Lake Regillus in the early fifth century. The brothers had a reputation for being excellent horsemen, and at the Capitol in the Eternal City we nowadays find statues of the Dioscuri and their horses. However, in Ostia and in other port cities Castor and Pollux were first of all worshipped as protectors of sailors. In fact, each year on 27 January Ostia celebrated a festival dedicated to the brothers. The ship from Alexandria that took Saint Paul the Apostle to Puteoli (see above) had the Dioscuri as a figurehead (Acts 28:11).
Given the high regard in which Castor and Pollux were held in Ostia, it should not come as a surprise that we see them depicted on a mosaic in the reception room of the House of the Dioscuri. The mosaic dates from the early fifth century, and that does come as a surprise. At the time Christianity was already the state religion of the Roman Empire and all the other cults had been officially banned. Nonetheless, the cult of the Dioscuri seems to have survived for a few more decades in Ostia, much to the chagrin of Pope Gelasius I (492-496). The Holy Father even explicitly stated that the cult had brought the maritime business very little (maria minime). In Rome itself the popularity of Castor and Pollux also seems to have diminished just slowly. In the sixth century Pope Felix IV (526-530) had a church built on the Forum Romanum for the Christian twins Cosmas and Damianus. This church is sometimes interpreted as the Christian answer to the cult of Castor and Pollux, whose temple stood just a stone’s throw away on that same Forum Romanum.
We continue our walk to the House of Bacchus and Ariadne, which was built during the reign of the emperor Hadrianus (117-138). The floor mosaics in the house date from the same era. Those in the dining room and the reception room are of excellent quality. The mosaic in the former room features a head of Medusa in the centre and several winged figures, vine scrolls and birds. The mosaic in the latter room is much larger and has a central scene on two levels. At the top Bacchus and Ariadne have been depicted, the couple after whom the house was named. Ariadne married Bacchus (or Dionysus), the god of wine, after the Athenian hero Theseus had rather unheroically abandoned her on the island of Naxos. Below them Amor/Cupido/Eros wrestles with Pan. The figures on the right are two Silenes, one of whom acts as a referee. On the table in the centre lies a laurel wreath for the victor.
Amor/Cupido/Eros returns in the House of Amor and Psyche, which is named after him. In this house it is the beautiful floor in opus sectile (see above) that catches the eye. The story of Amor and Psyche can briefly be summarised as the unintended love between an immortal god and a gorgeous mortal woman. The great painter Raphael (1483-1520) immortalised the story in beautiful frescoes in the Villa Farnesina in Rome. In one of the rooms of the house a statuette was found of the two lovers kissing passionately. The statuette has been replaced with a plaster replica; the original can be found in the Museo Ostiense degli Scavi di Ostia Antica.
Lastly, I will discuss the Hall of the Grain Measurers (mensores frumentarii). On a large mosaic in this building, which was laid in the third century and executed in black and white with just a few blue tesserae, we see six figures. A full discussion of the mosaic can be found on the marvellous Ostia Antica website. A very interesting figure is the small one in the centre. He is holding an instrument that was used to count sacks of grain. The instrument is also visible on a fresco from ca. 200-250 that depicts a ship called the Isis Giminia and that is currently in the Vatican Museums. Next to the small figure is the mensor. He has his left hand above a large barrel into which grain has been poured to be measured. In his right hand he is holding a rutellum, a stick or ruler used to level the grain. Above the six figures is a text that is unfortunately so damaged that it has basically become illegible. The Hall of the Grain Measurers and its mosaic make clear that Ostia was of vital importance for Rome’s grain supply. Admittedly the larger grain ships could only dock in Portus with its superior facilities, but plenty of smaller ships still left Ostia itself to sail down the river Tiber towards the capital. There, during the heyday of the Roman Empire, at least a million hungry mouths were screaming to be fed.
 Fik Meijer, Paulus, p. 316.