The Greek fleet then sailed to Byzantium, which they besieged and eventually captured. Control of both Sestos and Byzantium gave the allies command of the straits between Europe and Asia (over which the Persians had crossed), and allowed them access to the merchant trade of the Black Sea.

The aftermath of the siege was to prove troublesome for Pausanias. Exactly what happened is unclear; Thucydides gives few details, although later writers added plenty of lurid insinuations. Through his arrogance and arbitrary actions (Thucydides says "violence"), Pausanias managed to alienate many of the Allied contingents, particularly those that had just been freed from Persian overlordship. The Ionians and others asked the Athenians to take leadership of the campaign, to which they agreed. The Spartans, hearing of his behaviour, recalled Pausanias and tried him on charges of collaborating with the enemy. Although he was acquitted, his reputation was tarnished and he was not restored to his command.