In 146 BC, following the Achaean War, Greek cities were placed under control of the Roman governor of Macedonia, but they nonetheless retained part of their autonomy. It was not before the creation of the province of Achaea in 27 BC that they were officially incorporated into the Roman Empire.
The beginning of the 1st century BC undoubtedly marks a turning point for Eretria: like many Greek cities -and despite the relatively favorable treatment the Eretrians as well as the Athenians received from the Romans- Eretria took up the cause of King Mithridates VI Eupator, and found itself in the camp opposed to Rome. The conflict lasted from 88 to 85 BC, and culminated in the Roman proconsul L. Cornelius Sulla's sack of Athens on the night of March 1, 86 BC. Although literary sources do not mention the fate of Eretria, the layers of destruction that have been excavated by archaeologists show that the city was not spared.
The Augustan renewal
Almost two generations later, Eretria finally revived, with the accession of Augustus and the Principate in Rome. The historian Cassius Dio (LIV 7, 2) tells us that in 21 BC Augustus freed Eretria from Athenian sovereignty, to which it might have been subjected in 42 by a decision of the triumvir Mark Antony. The city recovered a form of autonomy and was freed from the heavy taxes imposed by Athens, which led to further growth.
New buildings were constructed, in particular near the House of the Mosaics, where an industrial quarter developed: a vat for processing Tyrian purple (a dyestuff for textiles), a chalk kiln for making mortar, running water, and -a novelty in Eretria- drains for waste water, all testify to a renaissance of activities in the city. The Temple of the Imperial Cult, the Sebasteion, was erected at the crossroads of the city's two main streets, while other public buildings, such as the Gymnasium and the Theater, were restored, offering further proof of renewed prosperity.
A modest city within the Roman Empire
A series of funeral stelai dating from the 1st to the 3rd centuries AD offer us a glimpse of a few residents of the modest city that was then Eretria -for instance, an Eretrian fisherman proudly represented along with the tools of his trade. Dwellings were henceforth concentrated at the foot of the acropolis, and perhaps on its slopes, whereas the heart of the classical city seems to have been reserved for graves, as is suggested in particular by an ornate tomb located near the Agora.
Eretria continued to strike its own coins until the end of the 2nd century AD, and this suggests that civic institutions functioned at least until that period. In addition, the base of a statue erected by the city to the Emperor Caracalla (212-217 AD) was found, as well as a later imperial base. But the economic and political center of gravity seems to have shifted to the city of Porthmos (modern Aliverion), where ca. 300 AD a copy of Diocletian's edict regarding maximum prices was displayed.