Achilles Tatius of Alexandria, Greek rhetorician, author of the erotic romance, The Adventures of Leucippe and Cleitophon, flourished about 450, perhaps later. The Suda, who alone calls him "Statius", says that he became a Christian and eventually a bishop like Heliodorus, whom he imitated, but there is no evidence of this. Photius, while severely criticizing his lapses into indecency, highly praises the conciseness and clearness of his style, which, however, is artificial and labored. Many of the incidents of the romance are highly improbable, and the characters, except the heroine, fail to enlist sympathy. The descriptive passages and digressions, although tedious and introduced without adequate reasons, are the best part of the work. The large number of existing manuscripts attests its popularity. (Editio princeps, 1601; first important critical edition by Jacobs, 1821; later editions by Hirschig , 1856; Hercher , 1858. There are translations in many languages; in English by Anthony Hodges , 1638, and R. Smith , 1855.)

Suidas also ascribes to this author an Etymology, a Miscellaneous History of Famous Men, and a treatise On the Sphere. Part of the last is extant under the title of An Introduction to the Phaenomena of Aralus. But if the writer is the prudentissimus Achilles referred to by Firmicus Maternus (about 336) in his Matheseos libri, iv. 10, 17 (ed. Kroll), he must have lived long before the author of Leucippe. The fragment was first published in 1567, then in the Uranologion of Petavius , with a Latin translation, 1630. Nothing definite is known as to the authorship of the other works, which are lost.