Bāj (from Persian bāzh; Ottoman Turkish bāc ) designates a tax, tribute, tithe, toll, customs due, or market tax. Bāzh was used in the Shāhnāma to refer to a tax and to the tribute paid in pre-Islamic times by the Eastern Roman Empire to the victorious Persians. The word was employed in the Ghaznavid and Selçuk (Saljūq) administrations both in the general sense of tax and to refer to specific taxes such as customs dues. It was also found in the Īlkhānid period, when it had several uses: tax in