Arcadian League

The Arcadian League was a federal league of city-states in ancient Greece. It combined the various cities of Arcadia, in the Peloponnese, into a single state. The league was founded in 370 BC, taking advantage of the decreased power of Sparta, which had previously dominated and controlled Arcadia. Mantinea, a city that had suffered under Spartan dominance, was particularly prominent in pushing for its founding. The league had its capital at the newly founded city of Megalopolis, where an assembly of 10,000 met as its governing body.

Although initially successful in resisting Spartan influence in Arcadia, the league was soon divided in the power struggles that engulfed Greece in the 4th century BC. Thebes, which had been instrumental in the founding of the league, soon came into conflict with Mantinea. At the Battle of Mantinea (362 BC), the cities of the league fought against each other, Mantinea fighting alongside Sparta and Athens, while Tegea and others sided with Thebes. Nonetheless, the league seems to have endured in some form down into the 3rd century.

Beginning in the 6th century BC and continuing through the 5th and early 4th centuries, Sparta dominated the Peloponnese, and compelled its neighors to join its Peloponnesian League and fight in its wars. This dominance naturally aroused anger amongst these neighboring states, and Sparta's allies proved themselves willing to rise up against their overlord on several occasions. In 418 BC, Mantinea joined a league of Peloponnesian democratic states that briefly pursued an anti-Spartan policy before being defeated at the Battle of Mantinea (418 BC).

After the end of the Peloponnesian War in 404 BC, Sparta, under king Agesilaus, took several opportunities over the ensuing years to discipline a number of restive allies. In 385 BC, the Spartans attacked Mantinea and forced the city to dissolve, splitting it into five separate villages, each of which was governed by a Spartan-backed oligarchy. Oligarchic governments throughout the rest of Arcadia also received Spartan support.

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