Polychares, Critias, Melobius, Hippolochus, Eucleides, Hieron, Mnesilochus, Chremon, Theramenes, Aresias, Diocles, Phaedrias, Chaereleos, Anaetius, Peison, Sophocles, Eratosthenes, Charicles, Onomacles, Theognis, Aeschines, Theogenes, Cleomedes, Erasistratus, Pheidon, Dracontides, Eumathes, Aristoteles, Hippomachus, Mnesitheides.One serious classical scholar has apparently written a book on them. I was not able to access his book. Doing what research I could as a mere Enlightened Layperson, using the Perseus Digital Library, and accepting guidance from Grote, Kagan, Wikipedia, and Google, I came up with a complete blank for about half of them. For others, I came up with only the barest minimum of information, discussing their actions under the Thirty, such as Mnesitheides took part in the arrest of Lysias and inspected his shield factory. Still, a little background information can be gleaned about a few of the Thirty, and at least some conjecture is possible about others.
Clearly at the time they took power, Theramenes would have been the most eminent and the best known to his countrymen. Theramenes had a distinguished father, Hagnon, founder of the colony of Amphipolis. Thucydides calls him "a good speaker." Indeed, he as been described as a distinguished orator and teacher of the later orator Isocrates. He was one of the Four Hundred who overthrew the democracy, as was his father. His role in overthrowing the oligarchy and restoring the democracy, winning important naval victories, and negotiating the peace with Sparta have already been discussed. Athenians would probably have assumed that he was the leader of the Thirty.
While most of the Thirty were returning exiles from the hardcore wing of the 400, Theramenes was not the only exception. Chremon was serving in the Council before Athens surrendered and arranged to have Cleophon tried by the Council instead of by a jury in the interests of removing an obstacle to peace* and arranging the arrest of Strombichides as another obstacle. Chremon went on to serve in the Thirty while his colleague in these actions, Satyrus, who Lysias incorrectly names as another of the Thirty, was leader of the Eleven, i.e., the executions of the Thirty. Xenophon describes him as the "most audacious and shameless" of the executioners.
Aristotle and Lysias both confirm that it was Dracontides who prepared the resolution to the Assembly instituting the Thirty. Neither says whether he had been in exile before, but it seems unlikely that they would have given a role like this, intended for keeping up appearances, to a newly returned exile.
Once an ardent democrat, Charicles ranked with Peisander as the worst witch hunters when the herms were mutilated, insisting that it was not the work of a small criminal clique, but an attempt to overthrow the democracy. The two of them were in large part responsible for scope of moral panic that followed and no doubt alienated many from the democracy. Tantalizingly, Thucydides speaks of a general/admiral by that name soon after Alcibiades defected who was sent to Argos to recruit fighters and who established a base in Laconia and then sailed home, leaving it in the hands of the Argives. (The base was abandoned as unaffordable after the Syracusan disaster). Was this the same Charicles? Given that most leading politicians of the time were also military commanders, it seems most likely. I found nothing on his role in the Four Hundred or whether he was exiled.
Thucydides mentions a general/admiral by this name. He was in the force that besieged Miletus, but later withdrew to Samos. He is last seen sailing against Chios. We hear nothing further of his career, or whether he took part in the coup. Certainly the commanders at Samos in general joined the conspiracy, but we do not know if Onomocles was still one of them. In short, it seems likely but by no means certain that he was among the commanders who staged the 411 BC coup and went into exile afterward.
This was not the tragic playwright, of course, who died shortly before the war ended. Thucydides mentions a general named Sophocles who served circa 426-424 BC.** This Sophocles was ordered to Sicily (in 426-425 BC, ten years before the major and disastrous invasion) but was delayed by storm and instead took part in the brilliant capture of Pylos. Sent to Sicily again the next year, he stopped at Corcyra just as the oligarchic faction was defeated and agreed to be taken to Athens. However, they were caught trying to escape, so Sophocles handed them over to the democrats to be slaughtered. Thucydides blames him for encouraging the democrats by making clear that he did not want to be bothered with transporting the prisoners. He was sent to Sicily to intervene in a war there. Wanting to avoid such intervention, the parties ended the war, so there were no grounds for intervention. Sophocles was put on trial for being bought off and exiled (424 BC). This could be the Sophocles who was one of the Thirty. Certainly his exile would not have made him fond of the democracy, and his brutal dealings with the oligarchs on Corcyra would not preclude him later being equally brutal with democrats. But I am inclined to think that the Sophocles of the Thirty was a different Sophocles simply because this one had been out of action for twenty years by the time the Thirty took over.
A Charmides, son of Aristotles was falsely accused of vandalizing the herms.*** Charmides appears to be the one who convinced Andocides to come clean about what he knew. We have no way of knowing whether this Aristotles was the father of that same Charmides although, if so, his son's unjust arrest cannot have endeared the democracy to him. We do know that he was one of the hard line faction of the 400, who was prepared to build a fort to be turned over to the Spartans in order to preserve their power, and who Theramenes thwarted. As such, he would necessarily have gone into exile when the 400 were overthrown. Indeed, he was with Lysander when Theramenes attempted to negotiate with him. It was Aristotles Lysander sent to report on the negotiations to the Ephors.
He was a ship captain in the Hellespont at the time the 400 staged their coup. Upon learning of the coup he deserted (presumably after he failed to win his crew over to it). He had been in exile ever since.
Critias, it would soon become apparent, was the real leader of the Thirty. Our information about him before that is limited, but he was important enough to deserve an entire post of his own.
Aristotle says that when the 400 seized power in 411 B.C., a Melobius was the main speaker on behalf of the resolution that allowed the 400 to draw up their constitution. Nothing further is known about his role under the 400. It seems most likely that he was of the hard line faction that went into exile, and most likely that this is the same Melobius who was one of the Thirty. But it is not certain. When Lysias was arrested, Melobius took part in the inspection of his shield factory. He even stole the earrings out of the ears of Lysias' brother's wife.
MnesilochusA Mnesilochus served as archon under the 400. Once again, it seems most likely, though by no means certain, that Mnesilochus the archon went into exile when the 400 were overthrown and was one of the Thirty.
*It is clear from this speech that Cleophon was a highly controversial figure, even among democrats.
**Sophocles son of Sostratides, and thus not the same as the tragic playwright, who was Sophocles son of Sophilus.
***Not the same Charmides who appears in Plato and held office under the Thirty. That was Charmides son of Glaucon.