The Roman armies have fared badly against the Sassanid Persians during the Anastasian War.
According to the Syriac Chronicle of Zacharias Rhetor, also known as Zacharias of Mytilene, the Roman generals blamed their difficulties on the lack of a strong base in the area, as opposed to the Persians, who held the great city of Nisibis (which until its cession in 363 had served the same purpose for the Romans).
Therefore, in 505, while the Persian King Kavadh I is distracted in the East, Emperor Anastasius I decides to rebuild the village of Dara, only eighteen kilometers westwards from Nisibis and just five kilometers from the actual border with Persia, to be "a refuge for the army in which they might rest, and for the preparation of weapons, and to guard the country of the Arabs from the inroads of the Persians and Saracens".
Masons and workers from all over Mesopotamia are gathered and work with great haste.
The new city is built on three hills, on the highest of which stands the citadel, and endowed with great storehouses, a public bath, and water cisterns.
It takes the name Anastasiopolis and becomes the seat of the Roman dux Mesopotamiae.