Alexander's conduct caused renewed intervention; in 364 he was defeated at Cynoscephalae by the Thebans, although the victory was dearly bought by the loss of Pelopidas, who fell in the battle.
Callicratidas pronounced against the enslavement of Greeks by Greeks, but violated his own principle, to which, however, Epaminondas and Pelopidas appear to have been faithful.
After the battle of Leuctra, when the power of Thebes was founded by Epaminondas, Pelopidas went to Susa (367) and restored the old alliance between Persia and Thebes.
On the other hand the lack of good harbours hindered its maritime development; and the Boeotian nation, although it produced great men like Pindar, Epaminondas, Pelopidas and Plutarch, was proverbially as dull as its native air.
In 374 Pelopidas restored the Theban dominion.
In the consequent wars with Sparta the Theban army, trained and led by Epaminondas and Pelopidas, proved itself the best in Greece.
In 369, in response to a petition of the Thessalians, Pelopidas was sent with an army against Alexander, tyrant of Pherae.
Next year Pelopidas was again called upon to interfere in Macedonia, but, being deserted by his mercenaries, was compelled to make an agreement with Ptolemaeus of Alorus.
In 367 Pelopidas went on an embassy to the Persian king and induced him to prescribe a settlement of Greece according to the wishes of the Thebans.
Plutarch and Nepos, Pelopidas; Diodorus xv.