The Spartans originated as Dorian invaders who settled in the Peloponnese region in the late 8th century BC. Under the reforms of the legendary lawgiver Lycurgus, Sparta developed a unique social and political system centered around a highly trained citizen-soldier class. All male Spartan citizens underwent an intensive agoge education program and were obligated to the military. The Spartan economy relied on subjugated populations of helot slaves who farmed the land to provide food for the Spartan messes. Through this system, Sparta was able to field a powerful professional army and establish itself as the dominant military power in ancient Greece during the classical era.