Britannica Sources used in this answer

Why were the Persian forces dependent on their fleet during Xerxes’ invasion?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Herodotus Herodotus, detail of a Roman herm probably copied from a Greek original of the first half of the 4th century bce; in the National Archaeological Museum, Naples.

During the invasion of Greece in 480 BCE, the Persian forces under Xerxes were heavily dependent on their fleet because it was essential for provisioning the massive land army as it advanced.1

Because the Persian army was so vast, it could not rely solely on local resources or land-based supply lines to sustain its march through Greece. Consequently, the fleet had to move in coordination with the land forces to ensure they remained supplied. This logistical necessity meant that the success of the entire invasion was inextricably linked to the security and mobility of the navy. When the Persian fleet was defeated at the Battle of Salamis, the logistical support for the invasion was severely compromised, forcing Xerxes to retreat to Asia and leaving the remaining land forces under Mardonius to face the Greek coalition alone.123