Back to menu

Late antiquity

During the first 150 years of its existence Portus was a district of Ostia. From an inscription (Thylander B336) has been deduced, that Constantine made it an independent city: Civitas Flavia Constantiniana, usually referred to as Portus Romae however. Portus already had its own bishop in 314 AD, who was present at the Council of Arles. The city was destroyed by Alaric and the Goths in 408 AD, and by the Vandals, led by their king Gaeseric, in 455 AD.

In spite of this, Portus remained an important harbour. However, the horrea were abandoned in the fifth and sixth century: they were incorporated in the city wall (built c. 400 AD or later), they collapsed, and finally they were used for burials. From now on storage took place only in horrea in Rome.

Portus was captured by the Goths in 537 AD. This was described in great detail by Procopius (see the section Ancient written sources - Texts). In the eighth century Trajan's basin became inaccessible due to silt. In the ninth century there were invasions by the Saracens. These led to the foundation in 842 of the fortified settlement Gregoriopolis to the east of Ostia, by pope Gregorius IV. Pope Leo IV (847-855) restored the city wall of Portus. The last year in which we know that the harbour was still in use is 879 AD. The Fossa Traiana was no longer navigable in the twelfth century.

Reconstruction drawing of Trajan's harbour, seen from the north.
Click to enlarge. Testaguzza 1970, p. 154-155.

[jthb - 22-May-2009]