In that same year the Turks and the Khazars poured through Bāb al-Abwāb and slew a great many Muslims in Armenia. The pilgrimage that year was led by [al-Sarī ibn ʿAbd Allah ibn al-Ḥārith ibn ʿAbbās ibn ʿAbd al-Muṭṭalib, the deputy of Mecca, while the deputy of Medina was ʿAbd Allah ibn al-Rabīʿ al-Ḥārithī; over Kūfa was ʿĪsā ibn Mūsā; over Baṣra, Salm ibn Qutaybah; and over Egypt, Yazīd ibn Ḥātim].
[Then the year 146 AH began.]
During it the building of Madīnat al-Salām in Baghdad was completed, and al-Manṣūr took up residence there in Ṣafar of that year, whereas previously he had been living in al-Hāshimiyyah adjoining Kūfa. He had begun its construction the year before—some say in 144 AH; Allah knows best.
The reason that moved him to build the city was that, after the Rāwandiyyah had risen against him in Kūfa and Allah shielded him from their harm, a remnant of them remained and he feared for his army. He therefore left Kūfa in search of a site for a new capital. Travelling through the lands until he reached al-Jazīrah, he found no place more suitable than the present location of Baghdad: a spot to which the produce of both land and river is brought morning and evening, defended on either side by the Tigris and the Euphrates so that no one can reach the caliph’s quarter except by a bridge. Al-Manṣūr spent several nights there before any building began and observed that the winds blew through it night and day [without any stifling heat or dust] (1); he perceived the excellence of the ground and the purity of its air.
At the site there had been villages and monasteries belonging to Christian monks and others; Abū Jaʿfar ibn Jarīr (2) has listed them all in detail by name and number. Al-Manṣūr then ordered the city to be laid out. They marked its plan for him with ashes, and he walked through its streets and lanes and was pleased. He assigned each quarter to a commander charged with its construction and summoned from every land labourers (3), craftsmen, and engineers, until thousands of them were gathered before him. He himself was the first to lay a brick with his own hand, saying:
“In the name of Allah; all praise is for Allah. ‘Indeed, the earth belongs to Allah; He causes to inherit it whom He wills of His servants, and the outcome is for the God-fearing.’ [al-Aʿrāf 7:128].”
He then declared, “Build, with the blessing of Allah,” and commanded that the city be circular, the thickness of its wall being fifty cubits at the base and twenty cubits at the top.