He took a leading part in expelling the Spartans from Thebes, B.C. 379; and from this time until his death there was not a year in which he was not intrusted with some important command.
In 371 he was one of the Theban commanders at the battle of Leuctra, so fatal to the Lacedaemonians, and joined Epaminondas in urging the expediency of immediate action. In 369 he was also one of the generals in the first invasion of the Peloponnesus by the Thebans. In 368 Pelopidas was sent again into Thessaly, on two separate occasions, in consequence of complaints against Alexander of Pherae. On his first expedition Alexander of Pherae sought safety in flight, and Pelopidas advanced into Macedonia to arbitrate between Alexander II. and Ptolemy of Alorus. Among the hostages whom he took with him from Macedonia was the famous Philip, the father of Alexander the Great. On his second visit to Thessaly, Pelopidas went simply as an ambassador, not expecting any opposition, and unprovided with a military force. He was seized by Alexander of Pherae, and was kept in confinement at Pherae till his liberation in 367 by a Theban force under Epaminondas.
In the same year in which he was released he was sent as ambassador to Susa to counteract the Lacedaemonian and Athenian negotiations at the Persian court.
In 364 the Thessalian towns again applied to Thebes for protection against Alexander, and Pelopidas was appointed to aid them. His forces, however, were dismayed by an eclipse of the sun (June 13), and, therefore, leaving them behind, he took with him into Thessaly only three hundred horse. On his arrival at Pharsalus he collected a force which he deemed sufficient, and marched against Alexander, treating lightly the great disparity of numbers, and remarking that it was better as it was, since there would be more for him to conquer. At Cynoscephalae a battle ensued, in which Pelopidas drove the enemy from their ground, but he himself was slain as, burning with resentment, he pressed rashly forward to attack Alexander in person.
The Thebans and Thessalians made great lamentations for his death, and the latter, having earnestly requested leave to bury him, celebrated his funeral with extraordinary splendour. (Harpers Dictionary of Classical Antiquities, 1898)
A Theban general and statesman, son of Hippoclus. He was descended from a noble family, and inherited a large estate, of which he made a liberal use. He lived always in the closest friendship with Epaminondas, to whose simple frugality, as he could not persuade him to share his riches, he is said to have conformed his own mode of life.