(Ἀγησίπολις), king of Sparta, the twenty-first of the Agids beginning with Eurysthenes, succeeded his father Pausanias, while yet a minor, in B. C. 394, and reigned fourteen years. He was placed under the guardianship of Aristodemus, his nearest of kin. He came to the crown just about the time that the confederacy (partly brought about by the intrigues of the Persian satrap Tithraustes), which was formed by Thebes, Athens, Corinth, and Argos, against Sparta, rendered it necessary to recall his colleague, Agesilaus II., from Asia; and the first military operation of his reign was the expedition to Corinth, where the forces of the confederates were then assembled. The Spartan army was led by Aristodemnus, and gained a signal victory over the allies. (Xen. Hell. 4.2.9.) In the year B. C. 390 Agesipolis, who had now reached his majority, was entrusted with the command of an army for the invasion of Argolis. Having procured the sanctions of the Olympic and Delphic gods for disregarding any attempt which the Argives might make to stop his march, on the pretext of a religious truce, he carried his ravages still farther than Agesilaus had done in B. C. 393; but as he suffered the aspect of the victims to deter him from occupying a permanent post, the expedition yielded no fruit but the plunder. (Xen. Hell. 4.7.2-6; Paus. 3.5.8.) In B. C. 385 the Spartans, seizing upon some frivolous pretexts, sent an expedition against Mantincia, in which Agesipolis undertook the command, after it had been declined by Agesilaus. In this expedition the Spartans were assisted by Thebes, and in a battle with the Mantineans, Epaminondas and Pelopidas, who were fighting side by side, narrowly escaped death. He took the town by diverting the river Ophis, so as to lay the low grounds at tlie foot of the walls under water. The basements, being made of unbaked bricks, were unable to resist the action of the water. The walls soon began to totter, and the Mantineans were forced to surrender. They were admitted to terms on condition that the population should be dispersed among the four hamlets, out of which it had been collected to form the capital. The democratical leaders were permitted to go into exile. (Xen. Hell. 5.2.1_7; Paus. 8.8.5; Diod. 15.5, &c.; Plut. Pel. 4; Isocr. Paneg. p. 67a, De Pace, p. 179c.)

Early in B. C. 382, an embassy came to Sparta from the cities of Acanthus and Apollonia, requesting assistance against the Olynthians, who were endeavouring to compel them to join their confederacy. The Spartans granted it, but were not at first very successful. After the defeat and death of Teleutias in the second campaign (B. C. 381) Agesipolis took the command. He set out in 381, but did not begin operations till the spring of 380. He then acted with great vigour, and took Torone by storm; but in the midst of his successes he was seized with a fever, which carried him off in seven days. He died at Aphytis, in the peninsula of Pallene. His body was immersed in honey and conveyed home to Sparta for burial. Though Agesipolis did not share the ambitious views of foreign conquest cherished by Agesilaus, his loss was deeply regretted by that prince, who seems to have had a sincere regard for him. (Xen. Hell. 5.3. 8-9, 18-19; Diod. 15.22; Thirlwall, Hist. of Greece, vol. iv. pp. 405, 428, &c, v. pp. 5, &c. 20.)