However, as happened to many prominent individuals in the Athenian democracy, Themistocles's fellow citizens grew jealous of his success, and possibly tired of his boasting. It is probable that in early 479 BC, Themistocles was stripped of his command; instead, Xanthippus was to command the Athenian fleet, and Aristides the land forces. Though Themistocles was no doubt politically and militarily active for the rest of the campaign, no mention of his activities in 479 BC is made in the ancient sources. In the summer of that year, after receiving an Athenian ultimatum, the Peloponnesians finally agreed to assemble an army and march to confront Mardonius, who had reoccupied Athens in June. At the decisive Battle of Plataea, the Allies destroyed the Persian army, while apparently on the same day, the Allied navy destroyed the remnants of the Persian fleet at the Battle of Mycale. These twin victories completed the Allied triumph, and ended the Persian threat to Greece.