Xerxes II (Old Persian Khšayâršâ) and Sogdianus: kings of the ancient Achaemenid empire. Xerxes ruled forty five days in the first months of 423 BCE; Sogdianus ruled for six months and fifteen days.
Our only source for the reign of Xerxes II and Sogdianus is the Greek author Ctesias of Cnidus, one of the most unreliable writers from Antiquity. In the eighteenth book of his History of the Persians, he states that Xerxes II was the only lawful son of king Artaxerxes I and queen Damaspia (who is otherwise unknown); Xerxes had been appointed as crown prince (mathišta).note[Ctesias, History of the Persians 46-51.] When Artaxerxes and Damaspia died on the same day, he succeeded to the throne. The last cuneiform tablet (found in Nippur) from the reign of Artaxerxes I is dated 24 December 424; there are no tablets from the reign of Xerxes II.
However, one of his half-brothers, Sogdianus, the son of Artaxerxes and a Babylonian woman named Alogyne, conspired against him. Ctesias mentions two other conspirators by name: Pharnacyas and Menostanes. On the forty-fifth day of his reign, Xerxes was killed when he was drunk. Sogdianus became king.
On hearing the news, another half-brother, Ochus, the son of Artaxerxes and another Babylonian woman named Cosmartidene, felt dishonored, because he was higher in rank. After all, he was not only a bastard son of Artaxerxes, but he was also his son-in-law, because he was married to Parysatis, the daughter of Artaxerxes and a third Babylonian concubine named Andia. He refused to do homage to Sogdianus; instead, he conspired with the commander of the cavalry, Arbarios, and became king. His throne name was Darius II Nothus. Sogdianus had been king for six months and fifteen days. His co-conspirator Pharnacyas was executed and Menostanes committed suicide.
So far Ctesias. The first Babylonian tablet dated to Darius' rule is from 10 January 423. It is remarkable that there are no tablets dated to either Xerxes II or Sogdianus. Even worse, the period between 24 December 424 and 10 January 423 is too short for the reigns of both kings.
Probably Ochus and Sogdianus declared themselves kings at the same moment, when they heard of their father's death. If this is correct, the Achaemenid empire had for a brief time three kings: Xerxes II in the Persian heartland, Darius in Hyrcania (where he was satrap), Media, Babylonia and Egypt (where satrap Arsames sided with him), and Sogdianus probably in Elam.
It may be noted that Menostanes is known from the archive of the Murašû family from Nippur, a Babylonian city. It is probably no coincidence that the name Manuštânu disappears from their records almost immediately after the accession of Darius II. His domains passed to one Artahšar, who is probably the same as Artoxares, a Persian nobleman who sided with Darius.
S. Zawadzki, "The Circumstances of Darius II's Accession" in Jaarbericht Ex Oriente Lux 34 (1995-1996) 45-49