Following the domination of reformer Kleomenes in Sparta, the old hatred of Dorean Lakedemonioi was rekindled and became even greater due to the spectacular expansion of the "Second Achaic Confederation". That resulted in the encouragement of the Aitoloi who had been waiting for the right moment to take action against the Achaioi. As a consequence, there was a first conflict with the "Aitoliki Confederation" (240 – 229 b.c) followed by the so-called "Kleomenean War" (229 – 222 b.c.) and then by the "Allies War" (220 – 217 b.c.).
Those wars exhausted the conflicting powers at the same time that the Roman power became more and more threatening to the independence of the Greek cities.
Despite the temporary culmination of the "Achaic Confederation"’s power, the Romans were the ones who, since 191 b.c., were influencing the developments in the Greek cities,
aiming at diminishing the power of Achaioi and turning them into subordinates of their foreign policy.
In fact, the Romans were so provocative as to ask for the shrinking of the Achaic Confederation and its limitation to the geographical boundaries of Achaia, while at the same time they were able to bribe distinguished people of Achaia with the help of
money, like Kallikrates from Leondio.
Finally, the fatal blow for the Achaic Confederation came when the Roman armies devastated its army in the battle of Skarfeia in Lokrida (147 b.c.)
The next year, Greece was under the rule of the Roman general of Macedonia and was named Achaia because, according to Paphsanias, the Romans "…subjugated the Greeks with the help of Achaioi, who were at that time the rulers of Greece…". However, despite the cruelty of conqueror Lefkios Mommios towards the defeated, the destruction of Korinthos, the pulling down of the city walls and the destruction of Dymi in 115 b.c., the achaic cities and Patras in particular benefited from the Romans.
In 48 b.c., Julius Caesar established a military settlement of Roman veterans in Dymi, the so-called "Colonia Augusta Aroe Patrensis", which he declared a "free city", which could have its own administrative bodies and coins. The Romans turned Patras into a booming city.
Similar, if less great, development took place in Aigio, Dymi, Aigeira, Loussoi, Keryneia. etc., while coins were still cut in Kleitoras and Psofeida, and Kynaitha was the place were cut for the first time.
