Characteristic architectural forms

The functions of monumental architecture in the Seljuq period were considerably modified. Large congregational mosques were still built. The earliest Seljuq examples occur in the two major new provinces of Islam—Anatolia and northwestern India—as well as in the established Muslim region of western Iran. In some areas, such as the Eṣfahān region, congregational mosques were rebuilt, while in other parts of the Islamic world, such as Syria or Egypt, where there was no need for new large mosques, older ones were repaired and small ones were built. The latter were partly restricted to certain quarters or groups or were commissioned by various guilds, particularly in Damascus.

A curious side aspect of the program of building, rebuilding, or decorating mosques was the extraordinary development of minarets. Particularly in Iran, dozens of minarets are preserved from the 12th and 13th centuries, while the mosques to which they had been attached have disappeared. It is as though the visual function of the minaret was more important than the religious institution to which it was attached.

Small or large, mausoleums increased in numbers and became at this time the ubiquitous monument they appear to be. Most of the mausoleums, such as the tomb tower of Abū Yazīd al-Bisṭāmī (died 874) at Basṭām, were dedicated to holy men—both contemporary Muslim saints and all sorts of holy men dead for centuries (even pre-Islamic holy men, especially biblical prophets, acquired a monument). The most impressive mausoleums, however, like the one of Sanjar at Merv, were built for royalty. Pilgrimages were organized and in many places hardly mentioned until then as holy places (e.g., Mashhad, Basṭām, Mosul, Aleppo); a whole monastic establishment serving as a centre for the distribution of alms was erected with hostels and kitchens for the pilgrims.

Although enormously expanded, mosques, minarets, and mausoleums were not new types of Islamic architecture. The madrasah (school), however, was a new building type. There is much controversy as to why and how it really developed. Although early examples have been discovered in Iran, such as the 11th-century madrasah of Khargird, and at Samarkand (now in Uzbekistan), it is from Anatolia, Syria, and Egypt that most of the information about the madrasah has been derived. In the latter regions it was usually a privately endowed establishment reserved for one or two of the schools of jurisprudence of orthodox Islam. It had to have rooms for teaching and living quarters for the students and professors. Often the tomb of the founder was attached to the madrasah. Later madrasahs were built for two or three schools of jurisprudence, and the Mustanṣiriyyah in Baghdad was erected in 1233 to be a sort of ecumenical madrasah for the whole of Sunni Islam.

In the Seljuq period there occurred a revival of the hostel-like ribāṭ inside cities. Khānqāhs (monastic complexes), monasteries, and various establishments of learning other than formal madrasahs were also built.

An impressive development of secular architecture occurred under the Seljuqs. The most characteristic building of the time was the citadel, or urban fortress, through which the new princes controlled the usually alien city they held in fief. The largest citadels, like those of Cairo and Aleppo, were whole cities with palaces, mosques, sanctuaries, and baths. Others, like the citadel of Damascus, were simpler constructions. Occasionally, as in the Euphrates valley, single castles were built, possibly in imitation of those constructed by the Christian Crusaders. Walls surrounded most cities, and all of them were built or rebuilt during the Seljuq period.

Little is known about Seljuq palaces or private residences in general. A few fragments in Konya or in Mosul are insufficient to give a coherent idea about urban palaces, and it is only in Anatolia and in Central Asia that an adequate idea of other types can be obtained. Anatolian palaces are on the whole rather small villa-like establishments, but, in Afghanistan and Central Asia, excavations at Tirmidh, Lashkarī Bāzār, and Ghaznī have brought to light a whole group of large royal palaces erected in the 11th and early 12th centuries.

Commercial architecture became very important. Individual princes and cities probably were trying to attract business by erecting elaborate caravansaries on the main trade routes, such as Ribāṭ-i Malik, built between Samarkand and Bukhara in Uzbekistan. The most spectacular caravansaries were built in the 13th century in Anatolia. Equally impressive, however, although less numerous, are the caravansaries erected in eastern Iran and northern Iraq. Bridges also were rebuilt and decorated like the one at Cizre in Turkey.

The forms of architecture developed by the Seljuqs were remarkably numerous and varied considerably from region to region. Because the Iranian innovations dating from the 11th century and first half of the 12th century are the earliest and, therefore, probably influenced all other areas of the Seljuq empire, they will be discussed first.

Architecture in Iran

Even though it is not entirely typical, the justly celebrated Great Mosque of Eṣfahān was one of the most influential of all early Seljuq religious structures. Probably completed about 1130 after a long and complicated history of rebuildings, it consisted of a large courtyard on which opened four large vaulted halls known as eyvāns; the eyvāns created the compositional axes of each side of the court. On the side of the qiblah (which indicates the direction of the sacred shrine of the Kaʿbah, faced by the faithful during prayers), the hall of the main eyvān was followed by a huge cupola. The area between eyvāns was subdivided into a large number of square bays covered by domes. The Eṣfahān mosque also had a unique feature: on the north side a single domed hall positioned on the main axis of the building was in all probability a formal hall for princes to change their clothes before entering into the sanctuary of the mosque.

The two features of the Great Mosque at Eṣfahān that became characteristic of Seljuq mosques were the eyvān and the dome. The eyvān was an architectural element known already in Sasanian architecture that had been used in residential buildings from Egypt to Central Asia before the 11th century. In fact, the use of the eyvān was not restricted to just mosques; it also appears in palaces (Lashkarī Bāzār), caravansaries (Rebāṭ-e Sharaf), and madrasahs. The eyvān was, in other words, a unit of architectural composition that had no specific use and, therefore, no meaning. In the mosques of the 12th century, four eyvāns were used, at least in the clearly definable architectural school of western Iran (e.g., Ardestān, Zavāreh). This kind of composition had two principal effects. One was that the eyvāns centralized the visual effect of the mosque by making the courtyard the centre of the building. The other effect of this composition was that it broke up into four areas what had for centuries been a characteristic of the mosque: its single, unified space. The reasons for those developments are still speculative.

Whether large or small, cupolas or domes were used in mosques, caravansaries, and palaces. They were the main architectural features of almost all mausoleums, where they were set over circular or polygonal rooms.

Two characteristic Iranian architectural forms are not present in the Great Mosque of Eṣfahān but occur elsewhere in the city. One is the tower. Those narrow and tall (up to about 150 feet [50 metres]) were minarets, of which several dozen have been preserved all over Iran and Central Asia (such as the one at Jām). Shorter and squatter towers were mausoleums. Those were particularly typical of northern Iran. The other characteristic architectural type exists only in Eṣfahān in a much-damaged state. It is the pīshṭāq, a formal gateway that served to emphasize a building’s presence and importance.

Domes and eyvāns indicate that the central concern of Iranian construction during the Seljuq period was vaulting in baked brick, which became the main vehicle for any monumental construction (mud brick was used for secondary parts of a building, frequently for certain secular structures). A large and forcefully composed octagonal base developed the muqarnas squinch from a purely ornamental feature into one wherein both structural and decorative functions combined. In some later buildings, such as the mausoleum of Sanjar at Merv, a system of ribs was used to vault an octagonal zone. Seljuq architects sought to make their domes visible from afar and for that reason invented the double dome. Its outer shell was raised on a high drum, while the interior kept the traditional sequence: square base, zone of transition, and dome. Using this structural device, therefore, exterior height was achieved without making the exterior dome too heavy and without complicating the task of decorating the interior, always a problem in countries like Iran with limited supplies of wood for scaffolding. Domes along the eyvāns were another factor that contributed to the growing separation between the exterior and the interior view of a building. The construction of tall circular or polygonal minarets and high facades also indicate an emphasis on visibility from a distance.

Architectural decoration was intimately tied to structure. Two mediums predominated. One was stucco, which continued to be used to cover large wall surfaces. The other was brick. Originating in the 10th-century architecture of northeastern Iran, brick came to be employed as a medium of construction as well as a medium of decoration. The complex decorative designs worked out in brick often had a rigidly geometric effect. Especially cut shapes of terra-cotta and brick, frequently produced in unusual sizes, served to soften those geometric patterns by modifying their tactile impact and by introducing additional curved or beveled lines to the straight lines of geometry.

Paintings were used for architectural decoration, especially in palaces. From the second half of the 12th century, coloured tiles began to be utilized to emphasize the contour of a decorative area in a structural unit; tiles were not used to cover whole walls, however. There are also examples of architectural sculpture of animals and people.

Most of the decorative designs tended to be subordinated to geometry, and even calligraphic or vegetal patterns were affected by a seemingly mathematically controlled aesthetic. It has been suggested that those complex geometric designs were a result of an almost mystical passion for number theories that were popularized in 11th-century Iran by such persons as the scholar and scientist al-Bīrūnī or the poet-mathematician Omar Khayyam. But even if the impulses for geometric design were originally created at the highest intellectual level, the designs themselves rapidly became automatic patterns. Their quality was generally high, but a tendency toward facility can be observed in such buildings as Rebāṭ-e Sharaf.