Baghdad, Caliph al-Mansur (r.754–775) allotted important tracts of real estate to his
Khurasan military leaders. In the course of time, as Baghdad prospered and land
prices rose, the Khurasani came to constitute a new, exclusive, and jealous elite. At
the same time as they favored these groups, the Abbasids succeeded in centralizing
their control even more fully than the Umayyads had done. This is clearest in the
area of taxation. The Umayyads had demanded in vain that all taxes come to them.
But the Abbasid caliph al-Mu‘tasim (r.833–842) was able to control and direct
provincial revenues to his court in Iraq.
Control, however, was uneven. Until the beginning of the tenth century, the
Abbasid caliphs generally could count on ruling Iraq (their “headquarters”), Syria,
Khurasan, and Egypt. But they never had the Iberian Peninsula; they lost Ifriqiya
(today Tunisia) by about 800; and they never controlled the Berbers in the soft
underbelly of North Africa. In the course of the tenth century, they would lose
effective control even in their heartlands. That, however, was in the future (see
Chapter 4).
Whatever control the Abbasids had depended largely on their armies. Unlike the
Byzantines, the Abbasids did not need soldiers to stave off external enemies or to
expand outwards. (The Byzantine strategy of skirmish warfare worked largely
because the caliphs led raids to display their prowess, not to take territory. The
serious naval wars that took Sicily from Byzantium were launched from Ifriqiya,
independent of the caliphs.) Rather, the Abbasids needed troops to collect taxes in
areas already conquered but weakly controlled.
Well into the ninth century the caliphs’ troops were paid, but not mustered, by
them. Generals recruited their own troops from their home districts, tribes, families,
and clients. When the generals were loyal to the caliphs, this military system worked
well. In the dark days of civil war, however, when two brothers fought over the
caliphate (811–819), no one controlled the armies. After al-Ma’mun (r.813–833) won
this civil war, he had no reliable army to back him up. His brother and successor, al-
Mu‘tasim, found the solution in a new-style, private army. He bought and trained his
own slaves, many of them Turks and thus unrelated to other tribal groups. These
men were given governorships as well as military posts. They were the reason that al-
Mu‘tasim was able to collect provincial taxes so effectively. He could not foresee that
in time the Turks would come to constitute a new elite, one that would eventually
help to overpower the caliphate itself.
Under the Abbasids, the Islamic world became wealthy. The Mediterranean
region had always been a great trade corridor; in the ninth century, Baghdad, at the
