Artaxerxes IV (Old-Persian Artakhšaça): name of a Achaemenid king of the Persian empire, ruled 338-336. His real name was Arses.
Arses was a son of the Persian king Artaxerxes III Ochus (358-338), and succeeded his father. According to a Greek source, Diodorus of Sicily, the powerful eunuch Bagoas poisoned many members of the royal family, but a cuneiform tablet in the British Museum (BM 71537) suggests that the king died from natural causes. However this may be, it happened in September 338, and it is probable that Bagoas killed everyone to make sure that Arses, who is presented by Diodorus as some sort of a puppet king, became the new ruler of the Achaemenid empire. Alternatively, Arses ordered the executions himself. This is not uncommon.
From an inscription from Xanthus, we know that Arses accepted the same throne name as his father and grandfather, Artaxerxes.
The death of Artaxerxes III caused great upheavals in the Achaemenid empire and it is certain that Bagoas and Artaxerxes IV were unable to get a firm grasp on the situation. At least two satrapies revolted: Egypt, which had recently been conquered by Artaxerxes III, and Babylonia (although the evidence for the insurrection of Nidin-Bêl is meager). To add to these troubles, the king of Macedonia, Philip II, prepared an attack on Persia's possessions in what is now Turkey. His trusted general Parmenion crossed the Hellespont in the spring of 336, and several Greek cities sided with the invader.
Under these circumstances, it comes as no surprise that the Persian nobility was divided. Prince Artašata, a distant relative of Artaxerxes and satrap of Armenia, seems to exercised pressure. He was a powerful man and a formidable warrior, and he received support from several noblemen (e.g., Pharnabazus). Diodorus says that Artaxerxes wanted to remove Bagoas (text) and that this forced Bagoas to kill this king as well (summer of 336). The cuneiform text known as the Dynastic prophecy suggests that Artašata marched on Persepolis and seized the throne. Whatever may have happened, Artašata now became king under the name of Darius III Codomannus.
One of his first acts was the execution of Bagoas. For a few months there was a respite: there was a strong king who was able to reunite the kingdom, and Philip was murdered (October 336). Moreover, a Greek mercenary general in Persian service, Memnon of Rhodes, was able to push back Parmenion. However, Philip was succeeded by his young son Alexander the Great, who joined Parmenion (May 334), and launched the campaign that ended with the fall of the Achaemenid empire and the death of Darius III (330).
There is one badly damaged source, quoted here, that suggests that Artaxerxes decided to restore the Babylonian temples Esagila and Etemenanki. The project was executed by Alexander.
The reign of Artaxerxes IV Arses was short but important, because the seeds were sown for the ultimate downfall of Persia.