The work was originally written in the Punic language, and what has come down to us is a Greek translation of the original. The work is often referred to by the ancients, but we have no statement containing any direct information by means of which we might identify its author, Hanno, with any of the many other Carthaginians of that name, or fix the time at which he lived. Pliny (Plin. Nat. 2.67, 5.1, 36) states that Hanno undertook the voyage at the time when Carthage was in a most flourishing condition. (Punicis rebus florentissimis, Carthaginis potentia florente.) Some call him king, and others dux or imperator of the Carthaginians, from which we may infer that he was invested with the office of suffetes. (Solin. 56; Hanno, Peripl. Introd.) In the little Periplus itself Hanno says that he was sent out by his countrymen to undertake a voyage beyond the Pillars of Hercules, and to found Libyphoenician towns, and that he sailed accordingly with sixty pentecontores, and a body of men and women, to the number of 30,000, and provisions and other necessaries. On his return from his voyage, he dedicated an account of it, inscribed on a tablet, in the temple of Cronos, or, as Pliny says, in that of Juno. (Comp. Pomp. Mela, 3.9; Marc. Heracl. Epit. Artemid. et Menip. ; Ath. 3.83.) It is therefore presumed that our periplus is a Greek version of the contents of that Punic tablet.

These vague accounts. leaving open the widest field for conjecture and speculation, have led some critics to place the expedition as early as the Trojan war or the time of Hesiod, while others place it as late as the reign of Agathocles. Others, as Falconer, Bougainville, and Gail, with somewhat more probability, place Hanno about B. C. 570. But it seems preferable to identify him with Hanno, the father or son of Hamilcar, who was killed at Himera, B. C. 480. [HANNO, Nos. 1, 2.] The fact of such an expedition at that time had nothing at all improbable, for in the reign of the Egyptian king Necho, a similar voyage had been undertaken by the Phoenicians, and an accurate knowledge of the western coast of Africa was a matter of the highest importance to the Carthaginians. The number of colonists, 30,000, is undoubtedly an error either of the translator or of later transcribers. This circumstance, as well as many fabulous accounts contained in the periplus, and the difficulties connected with the identification of the places visited by Hanno, and with the fixing of the southernmost point to which Hanno penetrated, are not sufficient reasons for denying the genuineness of the periplus, or for regarding it as the product of a much later age, as Dodwell did.