The destructive incursions of the Gauls aggravated this financial predicament but they also weakened the declining military power of the Macedonians, something that the Achaioi were the first to realize, in particular the citizens of Patras.
So, when the Gaulean armies of Belgium devastated the Macedonian army (281 b.c), the citizens of Patras revolted against the Macedonian army. Then, with the initiation of Dymi and the active participation of Farres, Triteia or Tritaia and Patras a new Achaic federation was founded, the so-called "Second Acchaic Confederation", which was meant to be the protagonist in the following developments as it incorporated every Greek city and it operated on the principle of voluntary unification of Greece.
After several years of effort, 43 cities were incorporated in the "Second Achaic Confederation", that is almost the whole of the Peloponnese, with the exception of Sparta which joined them much later. During that time, the Hellenistic Age, the fortification of several main Achaic cities was completed, with the exception of Patras which only fortified its acropolis (where one may find its castle nowadays), against the advice of general Alkiviades who insisted on the protection of its port as well.
On the contrary, there was a great improvement on the defense of Aigio, Keryneia, Aigira, Aiges, Dymi, Tritaia, Psofida, Kleitoras and Paos.
