The invading horde is said to have consisted of Massagatae; but we can hardly be mistaken in regarding them as, in the main, of Tatar, or Turkoman blood, akin to the Usbegs and other Turanian tribes which still inhabit the sandy steppe.

Sapor considered the crisis such as to require his own presence; and thus, while civil war summoned one of the two rivals from Mesopotamia to the far West, where he had to contend with the self-styled emperors, Magnentius and Vetranio, the other was called away to the extreme East to repel a Tatar invasion.

A tacit truce was thus established between the great belligerents--a truce which lasted for seven or eight years.
The unfortunate Mesopotamians, harassed by constant war for above twenty years, had now a breathing-space during which to recover from the ruin and desolation that had overwhelmed them.

Rome and Persia for a time suspended their conflict.

Rivalry, indeed, did not cease; but it was transferred from the battlefield to the cabinet, and the Roman emperor sought and found in diplomatic triumphs a compensation for the ill-success which had attended his efforts in the field..