Achaia
With the decline of the Mycenaean centers, Achaians from the Argolid came and settled here, founding important cities. The region is named Achaia after them. Though politically insignificant through most of antiquity, it started to playa more dynamic role in 280 BC, when the Achaian Confederacy was created.In 146 BC the area fell to the Romans.
It embraced Christianity earlier than the rest of Greece (St. Andrew the Apostle preached in Patras and was martyred there). In 1205 it occupied center stage with the founding of the Principality of Achaia by the Franks. Before too long it passed to the hands of the Palaiologues who ruled the Peloponnese from Mistra; they were succeeded by the Turks in 1460.
For a short period (1687-1715), the area was a Venetian colony. It was liberated in 1828.