The Taygetos are a formidable natural barrier which have provided a refuge from, and a centre of resistance to, the various forces that have invaded and conquered Greece in the last two thousand years. The caves at Pirgos Dirou provide evidence of habitation in the area since the Stone Age and Homer's Iliad lists the towns of the region that supplied men and ships for the Trojan War during the Mycenaean (Bronze Age) period. The area was probably a refuge during the Dorian invasion of the Peloponnese and in Classical times most of the area was under the control of Sparta - a heritage of which most modern Maniats are very proud.
In the Hellenistic period, Sparta's power and domination  declined, Lakonia was repeatedly invaded and Philip V of Macedon penetrated deep into the Mani in 218 BC.  Twenty two years later he was defeated by the Romans who crushed Sparta the following year and made Gythio the main city of a league of free cities to counter-balance Spartan power and influence. This Union of Free Lakonian Cities was officially recognised by the Emperor Augustus and Pausanias in his travels in the second century AD described  these flourishing cities and other sites in his travels through the area.
In 330 AD , the Emperor Constantine made Byzantium his seat of Government and renamed the city Constantinople. His successor, Theodosius, kept the Empire formally intact but the two main cities, Rome and Constantinople, were polarizing on religious grounds. The diverging interpretations of the life and nature of Christ led to the formation of the Roman Catholic Church in the west and the Orthodox Church in the east. When Rome fell to Alaric and the Goths in 410, the eastern half of the Empire, including the Greek Peninsula, survived as The Byzantine Empire with Constantinople as its capital and the center of the Orthodox Church.
There is debate as to when the Mani was converted to Christianity but it is probable that isolated pockets on the coastal areas were converted in the 6th Century AD, prior to the less accessible mountain areas, and there is reference to the Mani being a Diocese in the 9th Century AD although complete conversion probably did not occur for another 100 years or so.
The Slavic invasions of the Peloponnese resulted in more people seeking refuge in the Mani and although these invaders did penetrate parts of the Mani Peninsula, they do not seem to have reached the southern area in any great force.