The first Artaxerxes is mentioned in (Ezra 4:7) and appears identical with Smerdis, the Magian impostor and pretended brother of Cambyses, who usurped the throne B.C. 522, and reigned eight months.
In (Nehemiah 2:1) we have another Artaxerxes. We may safely identify him with Artaxerxes Macrocheir or Longimanus, the son of Xerxces, who reigned B.C. 464-425.