Corinth remained a thriving city in Late Antiquity and the early Christian era. After the earthquakes in the 4th century and Gothic raids in 395/6, the city appears to have changed.

Over the following centuries the space it occupied was confined within the so-called Late Roman or Early Byzantine wall, while the earlier walled link to Acrocorinth was cut off. The 5^th and 6^th centuries saw the building of numerous large Christian basilicas with substantial sculpture decoration in Corinth and its environs, such as those at Lechaion, Kechrees, Kraneion, Kodratos and Skoutela.  Furthermore, parts of a building attributed to a centrally planned Martyrion have been identified to the northwest of the basilica at Kraneion.

Extensive cemeteries dating to the 6th and 7th century have been excavated in areas outside the walls, at the Asclepeion and the basilicas at Kodratos and Kraneion.

Excavated building remains from the transitional centuries indicate habitation around the above basilicas and in the area called Diabatiki, while the Roman forum was used for burials.

In the mid-Byzantine period Corinth emerged as an important administrative and commercial centre, as indicated by coins. The trade in olive oil, the famed local currants and locally produced silk, all of which are mentioned in sources, appears to have flourished in this period. Archaeological finds from the Roman Forum reveal a bustling city that boasted houses, baths, shops and monasteries, as well as potters’ workshops, goldsmiths and brass workers. Commercial activity in the city does not seem to have waned when the Franks arrived in the 13th century, while the number of Italian imported vessels found in the so-called Frankish quarter is impressive. From the 14^th century onwards, in the wake of several blows to the city, the last remaining population appears to have moved into Acrocorinth Castle.