In the continual struggle between Rome and Parthia for the control of Armenia, the Parthian kings had one great advantage; they were Arsacids, and could put their sons or brothers on the Armenian throne with the good-will of the people, thus strengthening their dynastic position without much cost in military force. Often, too, the Armenian kingship was obtained by Parthian princes, who fled after a family quarrel, or after deposition or other misfortune. One of these Armenian kings was Chosroes, who reigned in the time of Ardashir, the first king of Persia, before spoken of. It is not certain just who he was; some say a brother of Ardvan, the last king of Parthia; some say the son of Ardvan, who fled after his father's death. Anyway, he was a mortal enemy of Ardashir, and was at first supported by the Romans. Ardashir invaded Armenia, but was beaten later. Chosroes quarreled with the Romans, who withdrew their support, and assailed him, but he defeated them; and when Ardashir again invaded the country, Chosroes again drove him back. The old days of Tigranes seemed to have returned, and Armenia to be on the road again to unity and independence; and Chosroes was called the Great. Ardashir was furious at being baffled, and is said to have offered his daughter's hand and a share in the kingdom to any one of his leading nobles who would assassinate Chosroes. An Arsacid named Anag accepted the offer, though he had a wife already, and went with his family to Armenia, pretending to be in flight from Persian troops. Chosroes gave him a military escort into the province of Ardaz, where he lived for a time in the very place St. Thaddeus' bones were deposited. Later on, Anag removed to Vagharshabad (the present city of Etchmiazin, where the Armenian Catholicos resides), Chosroes' royal city. Here Anag seizing his opportunity, stabbed Chosroes to the heart. In his flight he was drowned in trying to cross the Aras, and his family were massacred by the soldiery.