Abstract

We can begin with a story. In his account of the reign of Harun al-Rashid, al-Tabari spends considerable time on the matter of Yahya ibn Abdallah. Scion of the family of ‘Ali ibn Abi Talib, Yahya was the leader of a group active in Daylam, a region in present-day Iran. Al-Rashid and other Abbasid leaders laid claim to the territory, but at the time (the 790s) they did not have effective control over it. Ever-sensitive to the challenge presented by sentiment favoring the house of ‘Ali, al-Rashid and his advisers devised a scheme by which the ruler of Daylam received payment for persuading Yahya to turn himself in. He did so, but only on the condition that al-Rashid provide him with a writtenaman, or guarantee of security.