But their moderation was not appreciated; and the Persian monarch, on learning that Rome would not restore the refugees, declared the peace to be at an end, and immediately made preparations for war.

The Romans had, however, anticipated his decision, and took the field in force before the Persians were ready.

The command was entrusted to a general bearing the strange name of Ardaburius, who marched his troops through Armenia into the fertile province of Arzanene, and there defeated Narses, the leader whom Varahran had sent against him.

Proceeding to plunder Arzanene, Ardaburius suddenly heard that his adversary was about to enter the Roman province of Mesopotamia, which was denuded of troops, and seemed to invite attack.

Hastily concluding his raid, he passed from Arzanene into the threatened district, and was in time to prevent the invasion intended by Narses, who, when he found his designs forestalled, threw himself into the fortress of Nisibis, and there stood on the defensive.
Ardaburius did not feel himself strong enough to invest the town; and for some time the two adversaries remained inactive, each watching the other.