High Quality Content by WIKIPEDIA articles! The Battle of Piraeus was fought in 403 BC between Athenian exiles who had defeated the government of the Thirty Tyrants and occupied Piraeus and a Spartan force sent to combat them. In the battle, the Spartans narrowly defeated the exiles, with both sides suffering appreciable casualties. After the battle, Pausanias arranged a settlement between the two parties which allowed the reunification of Athens and Piraeus, and the reestablishment of democratic government in Athens.