Phlius, an ancient independent city in N. E. Peloponnesus. Its territory, Phliasia, was bounded N. by Sicyonia, E. by Cleonse, S. by Argolis, and W. by Arcadia, and consisted of a small valley, 900 ft. above the sea, enclosed by mountains. The river Asopus flows through the middle of the plain. Phlius was a Doric state-, and usually governed by an aristocracy, although once subject to the tyrant Leon, a contemporary of Pythagoras. It sent 200 soldiers to Thermopylae and 1,000 to Platasa, and during the Peloponnesian war was the faithful ally of Sparta. Afterward a division arose in the city, and the friends of the Lacedaemonians were banished; but in 393 B. C. the Phliasians received from Iphicrates so severe a defeat that they were forced to admit a Lacedaemonian garrison for their defence. In 380 and 379 Phlius sustained from Agesilaus, at the head of a Spartan army, a siege of one year and eight months. Having surrendered, it remained faithful to Sparta during the Theban war, was governed by tyrants after the death of Alexander, and subsequently joined the Achaean league. In antiquity the wine of Phlius was famous. The ruins of the city, near the village of St. George, are of considerable extent, but present little more than the foundations.

In the present kingdom of Greece Phliasia forms part of the eparchy of Corinth, in the nom-archy of Argolis and Corinthia.