Themistocles was born into a non-aristocratic family in Athens. Despite his humble origins, he demonstrates remarkable intelligence and ambition from an early age. Plutarch highlights his cunning and erratic nature and his determination to make a lasting mark on Athens.

When Themistocles enters public life, his main rival is Aristides. In many ways, Aristides is the opposite of Themistocles: He is aristocratic, gentle, and well-educated. After the Greeks win the First Persian War in 490 BCE, Themistocles knows that the Persians will come back and resolves to prepare Athens, despite Aristides’s resistance. A key moment comes when the Athenians find silver in Laurium and Themistocles succeeds in convincing them to use the wealth from the new mines to build warships. As the fleet is built, Themistocles’s influence grows. He sponsors musicians and poets and makes a point of knowing every Athenian citizen by name. Eventually, he gets his rival Aristides ostracized (banished from the city for a period of 10 years).

When the Persian king Xerxes finally invades Greece in 480 BCE, Themistocles tries to convince the people of Athens to abandon the city and put their trust in their fleet, but nobody approves this plan. Eventually, as the Persians sweep through Greece, Themistocles is sent to meet the Persian fleet at Artemisium.