At last Artabanus defeated his rival completely and occupied Ctesiphon; Vonones fled to Armenia, where he was acknowledged as king, under the protection of the Romans.
But it shared the fate of its predecessor; when the empire was founded the Sassanids could no longer remain in Persis but transferred their headquarters to Ctesiphon.
Sarsar, the modern Abu-Ghurayb, leaves the Euphrates three leagues lower down and enters the Tigris between Bagdad and Ctesiphon.
The Nahr Malk or royal river, modern Radhwaniya, leaves the Euphrates five leagues below this and joins the Tigris three leagues below Ctesiphon; while the Kutha, modern Habl-Ibrahim, leaving the Euphrates three leagues below the Malk joins the Tigris ten leagues below Ctesiphon.
With his Palmyrene troops, 4 strengthened by what was left of the Roman army corps, he took the offensive against Shapur, defeated him at Ctesiphon, and in a series of brilliant engagements won back the East for Rome.