[3] After twelve years of fighting, Tiridates was defeated by Ardashir, who nonetheless withdrew his army, and left Armenia.

[3] Khosrov participated in his father's military campaigns against Ardashir, who was alarmed by their victories.

[4] Anak went to Vagharshapat (now just outside of Yerevan), where he won Khosrov's trust, and treacherously murdered the king, along with his wife.

The outraged Armenian nobles slew Anak and his entire family,[4] except for his infant son, Gregory,[4] who was taken to Cappadocia by his caretakers, Sopia and Yevtagh, who escaped the slaughter of Anak's family and eventually became the patron saint and first official head of the Armenian Apostolic Church, converting Armenia from paganism to Christianity in 301.

Tiridates may have instructed Agathangelos to write a biography on the life and kingship of Khosrov II.