Boeotia to recover the prisoners taken in that battle. With Boeotia in hostile hands, Phocis and Locris became untenable and quickly fell under the control of hostile oligarchs. In 446 BC, a more dangerous uprising erupted. Euboea and Megara revolted. Pericles crossed over to Euboea with his troops, but was forced to return when the Spartan army invaded Attica. Through bribery and negotiations, Pericles defused the imminent threat, and the Spartans returned home. When Pericles was later audited for the handling of public money, an expenditure of 10 talents was not sufficiently justified, since the official documents just referred that the money was spent for a "very serious purpose". Nonetheless, the "serious purpose" (namely the bribery) was so obvious to the auditors that they approved the expenditure without official meddling and without even investigating the mystery. After the Spartan threat had been removed, Pericles crossed back to Euboea to crush the revolt there. He then punished the landowners of Chalcis, who lost their properties. The residents of Histiaea, meanwhile, who had butchered the crew of an Athenian trireme, were uprooted and replaced by 2,000 Athenian settlers. The crisis was brought to an official end by the Thirty Years' Peace (winter of 446–445 BC), in which Athens relinquished most of the possessions and interests on the Greek mainland which it had acquired since 460 BC, and both Athens and Sparta agreed not to attempt to win over the other state's allies. Final battle with the conservatives In 444 BC, the conservative and the democratic factions confronted each other in a fierce struggle. The ambitious new leader of the conservatives, Thucydides (not to be confused with the historian of the same name), accused Pericles of profligacy, criticizing the way he spent the money for the ongoing building plan. Thucydides initially managed to incite the passions of the ecclesia regarding these charges in his favor. However, when Pericles took the floor, his resolute arguments put Thucydides and the conservatives firmly on the defensive. Finally, Pericles proposed to reimburse the city for all questionable expenses from his private property, with the proviso that he would make the inscriptions of dedication in his own name. His stance was greeted with applause, and Thucydides was soundly, if unexpectedly, defeated. In 442 BC, the Athenian public voted to ostracize Thucydides from the city for 10 years and Pericles was once again the unchallenged ruler of the Athenian