Themistocles (c. 524–459 BCE), is an Athenian politician and a general.

He is one of a new breed of politicians who had risen to prominence in the early years of the Athenian democracy, along with his great rival Aristides.

As a politician, Themistocles is a populist, having the support of lower class Athenians, and generally being at odds with the Athenian nobility.

Elected archon in 493 BCE, he takes steps to increase the naval power of Athens, which will be a recurring theme in his political career.

During the first Persian invasion of Greece, he fights at the Battle of Marathon, and is possibly one of the 10 Athenian strategoi (generals) in that battle.

In the years after Marathon, and in the run up to the second Persian invasion he becomes the most prominent politician in Athens.

He continues to advocate a strong Athenian navy, and in 483 BC he persuades the Athenians to build a fleet of 200 triremes; these would prove crucial in the forthcoming conflict with Persia.

During the second invasion, he is in effective command of the Greek allied navy at the battles of Artemisium and Salamis.

Due to subterfuge on the part of Themistocles, the Allies lure the Persian fleet into the Straits of Salamis, and the decisive Greek victory there is the turning point in the invasion, which is ended the following year by the defeat of the Persians at the Battle of Plataea.

After the conflict ends, Themistocles continues to be preeminent amongst Athenian politicians.

However, he arouses the hostility of Sparta by ordering Athens to be refortified, and his perceived arrogance begins to alienate him from the Athenians.

In 472 or 471 BCE he is ostracized, and goes into exile in Argos.

The Spartans now see an opportunity to destroy Themistocles, and implicate him in the treasonous plot of their own general Pausanias.

Themistocles thus flees from Greece, and travels to Asia Minor, where he enters the service of the Persian king Artaxerxes I.

He is made governor of Magnesia, and lives there for the rest of his life.

Themistocles dies in 459 BCE, probably of natural causes.

Themistocles's reputation was posthumously rehabilitated, and he was reestablished as a hero of the Athenian (and indeed Greek) cause.

Themistocles can still reasonably be thought of as "the man most instrumental in achieving the salvation of Greece" from the Persian threat, as Plutarch describes him.

His naval policies would have a lasting impact on Athens as well, since maritime power became the cornerstone of the Athenian Empire and golden age.

It was Thucydides's judgement that Themistocles was "a man who exhibited the most indubitable signs of genius; indeed, in this particular he has a claim on our admiration quite extraordinary and unparalleled.