Whenever I think of the Abbasid caliphs of Baghdad, one story about them elbows aside all others in my mind. In the early 840s, Caliph Mutawakkil badly wanted to see a wondrous cedar in the hills of Nishapur that was said to have been planted 1,400 years earlier by Zarathustra to commemorate the conversion of the local king to his creed. But Nishapur was months away by caravan in north-east Iran, and the caliph had no time to go there. So he decreed that the tree be brought to him. Writing about it some 200 years later, the Iranian courtier and historian Beyhaqqi the Elder was clearly appalled by the barbarity of this decision, even though he was a committed Muslim himself. He wrote:

Mutawakkil ordered the [Arab] governor of Nishapur that all the branches of the tree be wrapped in felt so that carpenters in Baghdad could erect them again for him to see, before he used the timber to build a new mansion. So the Zoroastrians of Khorasan gathered and told the