Megasthenes (gr.(Μεγασθένης) (c. 350 BC-290 BC) was a Greek traveller and geographer to whom the subsequent Greek writers were chiefly indebted for their accounts of India. Megasthenes was a friend and companion of Seleucus Nicator (Clem. Alex. Strom. i. p. 305, d), and was sent by that monarch as ambassador to Sandracottus (Chandragupta ), king of the Prasii, whose capital was Palibothra (Patataliptra), a town, probably, near the confluence of the Ganges and Sone in the neighbourhood of the modern Patna. (Strabo ii. p. 70, xv. p. 702; Arrian, Anab. v. 6, Ind. 5; Pliny. H. N. vi. 17. s.21.) We know nothing more respecting the personal history of Megasthenes, except the statement of Arrian (Anab. l. c.), that he lived with Sibyrtius, the satrap of Arachosia, who obtained the satrapies of Arachosia and Gedrosia, in B. C. 323. (Diod. xviii. 3.) Whether Megasthenes accompanied Alexander or not in his invasion of India, is uncertain. The time at which he was sent to Sandracottus, and the reason for which he was sent, are also equally uncertain. Clinton (Fasti Hell. vol. iii. p. 482, note z) places the embassy a little before B. C. 302, since it was about this time that Seleucus concluded an alliance with Sandracottus ; but it is no where stated that it was through the means of Megasthenes that the alliance was concluded ; and as the latter resided some time at the court of Sandracottus, he may have been sent into India at a subsequent period. Since, however, Sandracottus died in B. C. 288, the mission of Megasthenes must be placed previous to that year. We have more certain information respecting the parts of India which Megasthenes visited. He entered the country through the district of the Pentapotamia, of the rivers of which he gave a full account (Arrian, Ind. cc. 4, 8, &c.), and proceeded thence by the royal road to Palibothra, but appears not to have visited any other parts of India. (Comp. Strab. xv. p. 689.) Most inodern writers, from the time of Robertson, have supposed, from a passage of Arrian (pollakis de legei (Megasthenes) aphikesthai para Sandrakotton ton Indon Basilea, Anab. v. 6), that Megasthenes paid several visits to India, but since neither Megasthenes himself, nor any other writer, alludes to more than one visit, these words may simply mean that he had several interviews with Sandracottus during his residence in the country.
The work of Megasthenes was entitled ta Indika, and was probably divided into four books (Athen. iv. p. 153, e.; Clem. Alex. Strom. i. p. 305; Strab. xv. p. 687; Joseph. c. Apion. i. 20, Ant. x. 11. § 1). It appears to have been written in the Attic dialect, and not in the Ionic, as some modern writers have asserted; for in the passage of Eusebius (Praep. Ev. ix. 41), which has been quoted to prove that Megasthenes employed the Ionic dialect, the quotation from Megasthenes concludes with the word katoikisai and the remaining words are an extract from Abydenus (comp. Clinton, Fast. Hell. vol. iii. p. 483, note b.). Megasthenes is repeatedly referred to by Arrian, Strabo, Diodorus, and Pliny. Of these writers Arrian, on whose judgment most reliance is to be placed, speaks most highly of Megasthenes (Arrian, Anab. v. 5, Ind. 7), but Strabo (ii. p. 70) and Pliny (l. c.) treat him with less respect. Although his work contained many fabulous stories, similar to those which we find in the Indica of Ctesias, yet these tales appear not to have been fabrications of Megasthenes, but accounts which he received from the natives, frequently containing, as modern writers have shown, real truth, though disguised by popular legends and fancy. There is every reason for believing that Megasthenes gave a faithful account of every thing that fell under his own observation; and the picture which he presents of Indian manners and institutions is upon the whole more correct than might have been expected. Every thing that is known respecting Megasthenes and his work, is collected with great diligence by Schwanbeck, in a treatise entitled "Megasthenis Indica. Fragmenta collegit, commentationem et indices addidit E. A. Schwanbeck, Bonnae, 1846."