In tradition, Aristeas (3rd century B.C.) was an official of Ptolemy Philadelphus, the ruler who commissioned the translation of the Septuagint.
[Ptolemy] Philadelphus chose such a man for this responsibility and appointed him to the oversight of his most noble library. I speak of Aristeas, his confidential chamberlain, whom he also sent as his representative to Eleazar, with most magnificent gifts, in recognition of the translation of the sacred Scriptures. And this person also wrote the full history of the Seventy translators. Theonas of Alexandria (c. 300, E), 6.160.