Diaeus

Diaeus was probably a son of Diophanes of Megalopolis, who had been a successful general of the Achaean League in 192/91 BC and who was himself the son of another Diaeus. A member of the Arcadian aristocracy in the Achaean confederation, which comprised by then the entire Peloponnese, the younger Diaeus was elected strategos of the Achaean League in 150 BC, succeeding Menalcidas of Sparta. Menalcidas had been charged by Callicrates with a capital offence, but saved himself by gaining the support of Diaeus, whom he bribed with three talents. Diaeus was generally blamed for this and, trying to divert public attention away from his own conduct, he sought a quarrel with Lacedaemon.

The Lacedaemonians had appealed to the Roman senate over the possession of some disputed land. In response, the Roman senate had said that decisions on all causes, except those of life and death, rested with the great council of the Achaeans. Diaeus decided to ignore the exception included in the Roman response.

The Lacedaemonians accused him of lying and the dispute led to war. However, the Lacedaemonians found themselves no match for the Achaeans, and they sought to negotiate. Diaeus, affirming that his hostility was not directed against Sparta as a whole, but against those who had caused the disagreement, arranged for the banishment of 24 of Sparta's principal citizens. These men fled to Rome and sought Rome's refuge and protection. Diaeus travelled to Rome to oppose their claims, together with Callicrates, who died along the way.

The cause of the Spartan exiles was supported by Menalcides, who assured the Spartans, on his return, that the Romans had declared in favour of their independence, while an equally positive assurance to the opposite effect was given by Diaeus to the Achaeans. In truth, the Senate had made no final decision, but had promised to send commissioners to settle the dispute.

In 148 BC, war was renewed between the parties despite such action being prohibited by the Romans. However, Diaeus, who was again general of the Achaean league in 147 BC, did seek to obey Rome's prohibition by endeavouring to bring over the towns around Sparta by negotiation. When the decree of the Romans arrived, which severed Sparta and several other states from the Achaean league, Diaeus took a leading part in building Achaean indignation and in urging them to the acts of violence which caused war with Rome.

In autumn 147 BC, Diaeus was succeeded as general of the Achaean league by Critolaus. But the death of the latter before the expiration of his year in that office once more placed Diaeus in the key position. (This outcome was based on the law of the Achaeans, which provided in such cases that the predecessor of the deceased should resume his authority.) The size of Diaeus' army was increased with emancipated slaves and by the levy of the citizens, which Diaeus enforced strictly, though not impartially.

In the resulting action, Diaeus acted unwisely in dividing his forces. He sent some of them to garrison Megara and to check the advance of the Romans. Diaeus himself established his quarters in Corinth, and Metellus, the Roman general, advancing towards Corinth, sent forward ambassadors to offer terms. But Diaeus threw them into prison (though he afterwards released them for the bribe of a talent). Diaeus then had Sosicrates, the lieutenant-general, as well as Philinus of Corinth, tortured to death for having recommended negotiation with the Romans.

Being defeated by Lucius Mummius Achaicus before the walls of the city in the Battle of Corinth (146 BC), Diaeus made no further attempt to defend the city, but fled to Megalopolis, where he slew his wife to prevent her being captured by the enemy and then killed himself by poisoning. His death marked the end of the Achaean League as it was then dissolved by Lucius Mummius.

 This article incorporates text from a publication now in the public domain: Smith, William, ed. (1870). Dictionary of Greek and Roman Biography and Mythology. Missing or empty |title= (help)

(Polyb. xxxviii. 2, xl. 2, 4, 5, 9 ; Pans. vii. 12,&c.; Clinton, Fasti Hellenici, sub annis 149, 147, 146.)