spahbed

thumb|368x368px|Modern reconstruction of a late Sassanian era "Spahbed" or Military Commander

Spāhbad (also spelled spahbod) is a Middle Persian title meaning "army chief" or commander used chiefly in the Sasanian Empire. Originally there was a single spāhbad, called the , who functioned as the generalissimo of the Sasanian army. From the time of Khosrow I ( 531–579) on, the office was split in four, with a spāhbad for each of the cardinal directions. After the Muslim conquest of Persia, the spāhbed of the East managed to retain his authority over the inaccessible mountainous region of Tabaristan on the southern shore of the Caspian Sea, where the title, often in its Islamic form (; in ), survived as a regnal title until the Mongol conquests of the 13th century. An equivalent title of Persian origin, ispahsālār or sipahsālār, gained great currency across the Muslim world in the 10th–15th centuries.