on every shore of the Ægean. His younger brother, Philip, then a boy, afterwards the great Philip, father of the greater Alexander, is said to have accompanied Pelopidas in his return to Thebes; whether for advantage of education and to extend friendly connection, or, as later writers have affirmed, as a hostage to insure the performance of stipulated conditions. Pelopidas returning to his command in Thessaly, his usual success failed him. According to Diodorus and Plutarch, venturing as voluntary negotiator for his country within the power of the profligate tagus, he was seized and imprisoned. But Polybius imputes his misfortune to positive imprudence, and an expression of Demosthenes would imply that he was made prisoner in battle. Nor were the exertions of the Theban government to avenge him fortunate. The Bœotarchs, who had ventured far into Thessaly with an army said to have been eight thousand foot and six hundred horse, not finding the support expected from the Thessalian people, were reduced to retreat before the greater force of the tagus; and, in traversing the Thessalian plain pursued by a superior cavalry, they suffered severely. It is attributed to the ability of Epaminondas, serving in an inferior station, but called forth by the voices of the soldiers to supply the deficiencies of the generals, that the army was not entirely cut off. Negotiation, supported probably by arms, yet not without some concession, procured at length the release of Pelopidas, early in 367. AN EMBASSY TO PERSIA AND A CONGRESS AT THEBES [Sidenote: [368-367 B.C.]] The cordial support of Athens, the force of mercenaries to be added by Philiscus, the growing aversion among the Arcadians to the Theban cause, and the troubles in the northern provinces, with the pressure of the Thessalian arms upon the Theban confederacy, together seemed likely to restore a decisive superiority to Lacedæmon, at least within her peninsula; and then, judging from experience, it was not likely to be confined there. But the able directors of the Theban councils had observed that the first and perhaps the most powerful efficient of this change in circumstances had been negotiation with Persia; and they resolved to direct also their attention to Persia, and try if they could not foil the Lacedæmonians by negotiation still more effectually than by arms. A minister from Lacedæmon, Euthycles, was actually resident at the Persian court. Upon this ground a congress of the confederacy was summoned, and, in pursuance of a common resolution, Pelopidas was sent to Susa on the part of Thebes, accompanied by ministers, from Argos, Elis, and Arcadia. The Athenians, jealous of the measure, sent their ministers also, Timagoras and Leon.