Kefalonia is the largest of the Ionian Islands in western Greece. It is also a separate regional unit of the Ionian Islands region, and the only municipality of the regional unit. It was also a former Latin Catholic diocese Kefalonia–Zakynthos (Cefalonia–Zante) and short-lived titular see as just Kefalonia. The capital of Cephalonia is Argostoli.
An aition explaining the name of Cephallenia and reinforcing its cultural connections with Athens associates the island with the mythological figure of Cephalus, who helped Amphitryon of Mycenae in a war against the Taphians and Teleboans. He was rewarded with the island of Same, which thereafter came to be known as Cephallenia.
Cephalonia has also been suggested as the Homeric Ithaca, the home of Odysseus, rather than the smaller island bearing this name today. Robert Bittlestone, in his book Odysseus Unbound, has suggested that Paliki, now a peninsula of Cephalonia, was a separate island during the late Bronze Age, and it may be this which Homer was referring to when he described Ithaca. A project which started in the Summer of 2007 and lasted three years has examined this possibility.