Marcus returned to Rome immediately thereafter, and sent out special instructions to his proconsuls not to give the group any official reception. The Armenian capital Artaxata was captured in 163. At the end of the year, Verus took the title "Armeniacus", despite having never seen combat; Marcus declined to accept the title until the following year. When Verus was hailed as "imperator" again, however, Marcus did not hesitate to take the "Imperator II" with him. Occupied Armenia was reconstructed on Roman terms. In 164, a new capital, Kaine Polis ('New City'), replaced Artaxata. A new king was installed: a Roman senator of consular rank and Arsacid descent, C. Iulius Sohaemus. He may not even have been crowned in Armenia; the ceremony may have taken place in Antioch, or even Ephesus. Sohaemus was hailed on the imperial coinage of 164 under the legend : Lucius sat on a throne with his staff while Sohamenus stood before him, saluting the emperor. In 163, the Parthians intervened in Osroene, a Roman client in upper Mesopotamia centered on Edessa, and installed their own king on its throne. In response, Roman forces were moved downstream, to cross the Euphrates at a more southerly point. Before the end of 163, however, Roman forces had moved north to occupy Dausara and Nicephorium on the northern, Parthian bank. Soon after the conquest of the north bank of the Euphrates, other Roman forces moved on Osroene from Armenia, taking Anthemusia, a town south-west of Edessa. In 165, Roman forces moved on Mesopotamia. Edessa was re-occupied, and Mannus, the king deposed by the Parthians, was re-installed. The Parthians retreated to Nisibis, but this too was besieged and captured. The Parthian army dispersed in the Tigris. A second force, under Avidius Cassius and the III Gallica, moved down the Euphrates, and fought a major battle at Dura. By the end of the year, Cassius' army had reached the twin metropolises of Mesopotamia: Seleucia on the right bank of the Tigris and Ctesiphon on the left. Ctesiphon was taken and its royal palace set to flame. The citizens of Seleucia, still largely Greek (the city had been commissioned and settled as a capital of the Seleucid Empire, one of Alexander the Great's successor kingdoms), opened its gates to the invaders.