Wars between the Greeks and Persians lasted throughout the period
of the Persian Achaemenid dynasty (549-330 BC), although the term
Persian Wars refers more specifically to the wars of Persian kings
Darius I and Xerxes I, which ended in 478 BC. Conflict began with
the conquest of Lydia when Cyres the Great of Persia triumphed over
Croesus at Sardis in 547. Cyrus then swept along the coast of the
Aegean Sea, gaining control of the Ionian towns formerly subject to
Lydia. Most of these towns revolted, however, and had to be
subdued. The Persians then installed friendly tyrants, and peace
was maintained until the reign (521-486) of Darius, when the Ionian
towns again rebelled. Many of the tyrants were killed or expelled.
Supporting the revolt, Athens
sent a fleet in 499 to aid the rebels, but by 493 the uprising had
been suppressed. In 490, Darius sent a fleet with an invasion force
against Athens, but the Persian army was defeated in the Battle of
Darius's son and successor, Xerxes, determined to punish Athens,
invaded Greece in 480. At first successful, the huge Achaemenid
army, estimated at more than 100,000 troops, was delayed at
Thermopylae by Leonidas and his Spartan forces. Finding a path to
the rear of the Greeks, the Achaemenid army annihilated them and
marched to Athens, whose citizens had fled to nearby islands.
Although Athens was burned, the Greeks decisively defeated the
Persian fleet at Salamis. Xerxes returned to Persia, leaving an
army to subdue Greece. The following year, however, this army was
defeated at Plataea, ending the danger of Persian invasion.
For the next 30 years the Greeks fought under Athenian leadership,
winning back territory from the Persians in Thrace and Anatolia,
although Greek intervention in Egypt ended in disaster. Enmity
among the Greeks led to the Peloponnesian
War (431-404) between Athens and Sparta, during which the Persians played
one opponent against the other. In 411, Sparta made peace with the
Persians and recognized Persia's claims to the Ionian towns.
Clashes did not cease, however; the more comprehensive King's Peace
was made in 387-386, leaving under Achaemenid rule only those Greek
cities that were in Asia. This peace did not end Persian intrigues
with or against various Greek city-states, and many Greek
mercenaries served in Persian armies or navies. Only the conquests
of Alexander the Great ended the Achaemenid Empire and the wars
between Persia and Greece.
The Greek historian Herodotus provided the principal source of
information on the conflicts in his History. Another ancient Greek,
Xenophon, described an expedition (401) by Spartan mercenaries in
the service of the Persians in his Anabasis.