He, however, survived his elevation only a year.

Upon his decease, A.D.
413, Isdigerd selected for the viceroyship, not an Arsacid, not even an Armenian, but his own son, Sapor, whom he forced upon the reluctant provincials, compelling them to acknowledge him as monarch (A.D.
413-414).

Sapor was instructed to ingratiate himself with the Armenian nobles, by inviting them to visit him, by feasting them, making them presents, holding friendly converse with them, hunting with them; and was bidden to use such influence as he might obtain to convert the chiefs from Christianity to Zoroastrianism.

The young prince appears to have done his best; but the Armenians were obstinate, resisted his blandishments, and remained Christians in spite of all his efforts.

He reigned from A.D.414 to 418, at the end of which time, learning that his father had fallen into ill health, he quitted Armenia and returned to the Persian court, in order to press his claims to the succession.
Isdigerd died soon afterwards (A.D.419 or 420); and Sapor made an attempt to seize the throne; but there was another pretender whose partisans had more strength, and the viceroy of Armenia was treacherously assassinated in the palace of his father.