العواصم

Al-Awasim ("the Capitals") was a border region established by Harun al-Rashid, stretching from Antioch to the Euphrates, with its own internal administrative and military autonomy. ²

Al-Rashid separated it from the frontier districts of al-Jazira and Syria. It was called al-Awasim because it protects ("ta'sim") the borders from falling into the enemy's grip, and to distinguish it from the outer northern fortresses known as the thughur (frontier posts). ²

Manbij was its first capital, and then Antioch became it. Al-Rashid appointed his son al-Qasim as its governor. ²

Its task was to support the frontier posts with equipment, men, and provisions, and it was equipped with permanent garrisons and defensive supplies. ²

The Byzantines, in response, set up a defensive line made up of the two ranges of the Taurus mountains from the Euphrates to Cilicia. It had two sections: one from Melitene to Ayn Zarba, to face the Muslims coming from northern Iraq, and the other to face them from the direction of Syria. ³