He also founded a new capital in the central valley of the Araxes River called Artaxata (Artashat), which quickly grew into a major urban and commercial center.

[8] However, the discovery of boundary stones with Aramaic inscriptions in Armenia in which Artaxias proclaims himself to be an "Orontid king" and "the son of Zareh (Zariadres)" has proven that Artaxias and Zariadres were not Macedonian generals from outside of Armenia but members of the local Orontid dynasty, albeit probably belonging to different branches than the original ruling house.

[9][b] Different views exist on the question of whether the Zareh mentioned in Artaxias' Aramaic inscriptions is identical with the Zariadres who became ruler of Sophene according to Strabo.

Also matching with this evidence are two inscriptions found at the Orontid capital of Armavir which mention a king named Orontes and lament the death of an Armenian ruler killed by his own soldiers.

[7] While there are still questions about the dating of the Armavir inscriptions,[12] this evidence has been used to support the view that Artaxias, a local dynast, overthrew the Orontid king Orontes IV (r. 212 – 200 BC) at the instigation of Antiochus III.

[15] Soon after Antiochus was defeated by the Romans at the Battle of Magnesia in 191/190 BC, Artaxias and Zariadres revolted against the Seleucids and declared themselves independent kings in Greater Armenia and Sophene.

[19] Their conquests were not obstructed by the Seleucids during the reign of Antiochus' successor Seleucus IV (r. 187–175 BC), who decided not to wage any new wars.

[23][d] According to Strabo, the unification of these territories under Artaxias and Zariadres led the population of Greater Armenia and Sophene to "speak the same language," i.e., Armenian.

[29] According to the Armenian historian Movses Khorenatsi, Artaxias ordered the delimitation of villages and farmland; this has been confirmed by the discovery of boundary stones with Aramaic inscriptions in Armenia.

[19] Strabo and Plutarch report that the former Carthaginian commander Hannibal took refuge at the Armenian court and played a role in the establishment of the city, although this is unlikely to be true.

[19] Khorenatsi reports that Artaxias resettled residents from Eruandashat and Armavir to Artaxata and transferred the idols of Tir, Anahit, and various other statues from Bagaran.

[40] However, it is generally believed that the real historical basis for the story came from the invasion of Armenia by the Alans in the 1st century AD, during the reign of Tiridates I.

For example, in the epic (and thus also in Khorenatsi's history) the invasion of Armenia by the Alans is placed in Artaxias' time, when it actually occurred in the 1st century AD, under Tiridates I.

[47] The account of Artaxias' early life in the epic follows a pattern seen also in other epic traditions: Artaxias, who is a son of the Armenian king Sanatruk,[j] is the sole survivor of the massacre of his family by King Orontes; he is saved by his tutor Smbat Bagratuni and taken to live with shepherds (as in stories about Cyrus the Great and Ardashir I); he then returns to reclaim his kingdom with Persian help.

[54] The 19th-century Armenian poet Bedros Tourian wrote a play about Artaxias titled Ardashes Ashkharhagal (Artashes the Conqueror), which was first performed in 1870.