the major administrative center of the ῾Abbasid caliphate (750–1258 CE) and the capital of the modern state of Iraq (33°26′18′′ N, 44°23′9′′ E). The city was founded In 762 CE by the second ῾Abbasid caliph Abu Ja'far al-Mansur. Previously, the ῾Abbasid rulers had established the center of their administration at a number of sites in Iraq, each of which was called al-Hashimiyyah. It would appear that the ῾Abbasids preferred to build their administrative complexes in the vicinity of established urban centers, but they always left a discreet distance between an area reserved for the government and military and the urban population. In this way they hoped to provide for security while availing themselves of nearby goods and services. The pattern seems to have been employed at Baghdad as well.

The caliph's decision to seek a new location at which to build still another administrative center was conditioned by security needs. Al-Mansur's current administrative center was situated in the general vicinity of Kufah, a city known for its residual support of Shi῾i causes. After a lengthy search, in which he followed the course of the Tigris River as far as Mosul, the caliph decided to construct a palace complex at the junction of the Tigris and the Sarat Canal, the latter a constructed waterway that bifurcated from the Euphrates River. This particular location offered certain strategic and geographic advantages. The Sarat, which was deep enough to allow for commercial traffic, enabled the caliph to utilize Iraq's two major river systems: the Tigris and the Euphrates. Moreover, the city was astride the major overland highways and pilgrimage routes. Baghdad thus became the commercial as well as geographic epicenter of the newly established ῾Abbasid regime.

The palace complex itself was surrounded by three bodies of water: the Tigris and the upper and lower arms of the Sarat. The Tigris, a wide, undulating river, could not be forded at the site of the city. Throughout the history of Baghdad, movement across the Tigris was funneled through a series of pontoon bridges that could be cut from their moorings, denying potential enemies access to the caliph's flank. The built waterways similarly served as natural barriers in time of attack.

The first major structure to be erected was the Round City, called Madinat al-Salam. It was built on the site of an old hamlet on the west side of the river that was called Baghdad. That name was subsequently applied to the entire urban area. Before the founding of the ῾Abbasid city, there were a number of villages in the general area. These were divided among four administrative districts on both sides of the Tigris: Qatrabbul, Baduraya, Nahr Buq, and Kalwadha. A small market area known as the Tuesday Market was situated on both sides of the river, to service the inhabitants of the four districts.

The construction of a major edifice on a sparsely settled site required an organized and highly efficient set of work procedures. It was not until a large labor force had been assembled that construction was actually begun, and it took four years to complete all the major elements of the Round City, thus allowing the caliph time to transfer his old capital from near Kufah. With tens of thousands of workers assembling from the outlying districts and from areas even farther removed, the skilled and unskilled laborers, the artisans, and the military who kept order all required housing and access to established markets for services. Al-Mansur's capital therefore assumed a quality of permanence in places beyond the walls, even before the Round City was completed. The urban area around its original walls eventually developed into a sprawling complex of interdependent elements with markets, mosques, and cemeteries. The area below the Sarat Canal, which contained the Tuesday Market, developed into the great commercial suburb called al-Karkh and was inhabited by the general populace. The area north of the Sarat and beyond the Round City was originally set aside for billeting the army.

The Round City was not a conventional city. It contained no economic infrastructure whatsoever, and strict precautions were taken to limit access by the general populace. It was more correctly an enormous palace complex that housed the residence and mosque of the caliph, the residences of his younger children, the agencies of government, and residences for the government bureaucracy that staffed the agencies of government as well as a skeleton force of security personnel. The size of the complex, 450 ha (1,132 acres) was unprecedented. Though only a palace complex, it was, in fact, larger than any urban settlement in the Diyala plains, the area that was the vast hinterland of Baghdad.

The Round City consisted of four architectural elements: outer fortifications, an inner residential area of symmetrically arranged streets, a second inner area of government agencies, and, moving toward the center of the circle, an inner courtyard in which the caliph's palace and the adjoining Friday mosque were situated. The outer fortifications were two concentric walls separated by an intervallum. The inner wall, the city's major protective wall, was flanked by roundels. Access to the residential area and the central court was gained through four elaborate gateways and arcades beginning at the outer wall and extending to the circular court. The four gate complexes were situated along the central axis of the caliph's residence and thus formed the city's north-east, northwest, southeast, and southwest quadrants. They originally contained security forces protecting the approaches to the central court. The arcade system was symbolically, as well as functionally, an extension of the caliph's domain. The purpose of the Round City was to combine the caliph's residence and mosque with the agencies of government, the residences of the regime's public servants, and security forces. Access to the general public was restricted and movement to the central court carefully monitored.

The very size of the palace complex, and the large and exclusive population it contained, made it difficult to service and supply. As a result, various distributive outlets were permitted within the walls, but following a breach of security, the merchants who had been permitted entry into the city were removed. The caliph, aware that his original plan for discrete government and private sectors had been compromised, moved to a more modest residence outside the Round City, along the Tigris. The caliph had previously begun construction of a second palace complex across the river. This construction on the east side of the Tigris was completed by his son and successor, al-Mahdi In 776 CE. The new area, called ar-Rusafah, or Askar al-Mahdi, contained a magnificent palace and Friday mosque that was to serve as the residence of the heir apparent. When al-Mahdi came to power, he took up residence in the palace built expressly for him. Unlike the Round City, which had been partly chosen for its advantageous location near the Tuesday Market, the situating of ar-Rusafah was determined primarily by its strategic location opposite the government sector on the upper west side of the river. This created two problems: a lack of water and a lack of services in the absence of a major nearby market area. Al-Mahdi therefore extended feeder channels from a canal north of the city and established a major market near the Main Bridge. It was called the Thirst Market and was likened to the markets of al-Karkh.

In time, two large private neighborhoods were developed nearby: Bab at-Taq, near the main bridge connecting ar-Rusafah with west Baghdad, and al-Mukharrim, which extended southeast along the river. Subsequent caliphs, al-Hadi (d. 786 CE) and Harun al-Rashid (d. 809 CE), lived in individual palaces rather than large complexes. The reign of al-Rashid is generally considered the zenith of growth in Baghdad. The city then reached its greatest limits in surface area and population.

The caliph's untimely death In 809 brought his son al-Amin to power and plunged the Islamic state into a debilitating civil war. A second son, the heir apparent, al-Ma-'mun, dispatched an army against the capital and laid siege to it. The chronicles describe widespread devastation and suffering in graphic terms, but closer examination of these texts reveals that the damage is grossly overestimated: all the major structures that had been damaged were repaired and functioning shortly after the conflict ended.

Despite winning the battle for Baghdad, al-Ma'mun remained at his stronghold in the eastern province of Khurasan. When he finally did settle in the city, it was in a modest palace on the east side of the river. Even then, the caliph, who never felt comfortable in Baghdad, preferred to spend his time in Khurasan. When al-Ma'mun died In 833, he was succeeded by a third brother, Caliph al-Mu῾tasim, who also resided in a modest residence. The latter relied heavily on military contingents recruited from among Turkish captives. The unruly behavior of the Turks resulted in several altercations with the local populace, causing al-Mu῾tasim to leave the city altogether. The caliph then founded a rival administrative center at Samarra, about 96 km (60 mi.) upstream, along the Tigris. When the Caliph al-Mu῾tadid returned to Baghdad In 892, he built the first of a series of new caliphal palaces, collectively called the Dar al-Khilafah.

The new caliphal enceinte, which was situated in the southeast section of the urban area, is described in the sources in great detail. Magnificent residences, exquisitely appointed, and featuring unusual elements are mentioned that include a zoological garden and fantastic mechanical devices. This impressive architectural achievement was to be the last major caliphal construction effort. With the caliphate's declining fortunes, the city began to shrink in size and population. Beginning with the Buyid hegemony In 945, the caliphs were increasingly reduced to the role of figure-heads. The Buyids, indeed, went so far as to build a major series of palaces in the northeast section of the city above ar-Rusafah that was intended to rival the splendid residence of their de jure patrons. This construction was more than offset, however, by the breakdown of order and the decline of local neighborhoods. The chronicles describing the events of the tenth and eleventh centuries indicate a pattern of religious conflict, economic dislocation, and widespread decay. When Hülegü, the Mongol, conquered Baghdad In 1258, effectively ending the ῾Abbasid regime, he conquered a hollow shell of a once-proud city. Writing about Baghdad, the great geographer Yaqut (d. 1225 CE) describes a series of truncated neighborhoods at some distance from one another, where there had at one time been a continuous line of occupation. This pattern continued until the twentieth century.

The dimensions of the medieval city and the extent of its population are difficult to gauge. The sources give exact figures for the surface area in varying meteorological systems. If these figures are accurate, the city would have covered more than 7,000 ha (17,290 acres). This would make Baghdad five time larger than tenth-century Constantinople and thirteen times larger than Sasanian Ctesiphon, hitherto the largest city known in the Diyala plains. Although this figure reflects Baghdad's suburban districts as well, there is reason to believe that the greater metropolitan area was heavily occupied. There is no hint of any census in the sources, but various crude efforts were attempted to calculate the population, usually by the use of multipliers (i.e., the number of doctors, attendants at bathhouses, foods consumed, and so forth). The figures obtained from this method are, however, unreliable. In modern Baghdad, the density of occupation in the oldest neighborhoods is about 200 people per hectare, which agrees with the most conservative estimates for the population of medieval Constantinople. The physical and human dimensions of medieval Baghdad must have been vast by any standard of measurement, however, because the greater urban area did not represent a single city but a series of urban settlements collectively known as Baghdad.


  • Creswell, K. A. C. Early Muslim Architecture, vol. 1, Umayyads, A.D. 622–750 (1940). 2d ed. Oxford, 1969.
  • Herzfeld, Ernst, and Friedrich P. T. Sarre. Archäologische Reise im Euphrat- und Tigris-Gebiet. Vol. 2. Berlin, 1940.
  • Lassner, Jacob. The Topography of Baghdad in the Early Middle Ages: Text and Studies. Detroit, 1970.
  • Le Strange, Guy. Baghdad during the ῾Abbasid Caliphate. Oxford, 1900.
  • Salmon, Georges. L'introduction topographique à l'histoire de Baghdad. Paris, 1904.

Jacob Lassner