The domes of the Early Middle Ages (c. 500-1000) built by Arab Muslim and Western European Christian states, particularly in those areas recently under Byzantine control, were an extension of earlier Roman architecture. The early Islamic domes in the Syrian region as well as the Mausoleum of Theodoric in Italy are believed to have benefited from the work of Syrian craftsmen. The Dome of the Rock, an Umayyad Muslim religious shrine built in Jerusalem, was designed similarly to nearby Byzantine martyria and Christian churches. Domes were also built as part of Muslim palaces, throne halls, pavilions, and baths, and blended elements of both Byzantine and Persian architecture, using both pendentives and squinches. Domes were included as part of Muslim palaces prior to their use in mosques, where early domes were likely used to mark the place of the ruler during ceremonies.
In the Christian West, the influence of Byzantine architecture diminishes under Charlemagne, although his Palatine Chapel is a notable exception, being influenced by Byzantine models from Ravenna and Constantinople. It was used as a throne hall and mausoleum, and the octagonal dome would be very influential in the architecture of the successor states to the Carolingian Empire, inspiring copies into the 14th century. Circular churches in central Europe were usually royal chapels.
The Islamic architecture of al-Andalus included the earliest known example of the crossed-arch dome type in the Great Mosque of Córdoba, which was famous in the Islamic world, and it may have spread the type. In Egypt, a "keel" shaped dome profile was characteristic of Fatimid architecture. Fatimid palace architecture has not survived, but Fatimid mausoleums were mostly simple square buildings covered by a smooth or ribbed dome, with some urban examples including carved stucco decoration. The use of squinches became widespread in the Islamic world by the tenth and eleventh centuries.
Ostrogothic Kingdom
Although the chronology is uncertain for some examples, domes continued to be built in Italy throughout the Middle Ages. Dome construction appears to have stopped within the city of Rome in the middle of the 5th century, but there are dozens of Italian examples outside of Rome from the next few centuries. Continuing from late antiquity, domes in the early Middle Ages were built over centralized buildings such as baptisteries and martyria. The Albenga Baptistery was built as early as the mid-5th century in Italy.
The building projects of Theodoric the Great, the Ostrogothic king of Italy, largely continued existing architectural conventions. His Arian Baptistry in Ravenna (c. 500), for example, closely echoes the Baptistry of Neon built before it. The Mausoleum of Theodoric, however, was understood by contemporaries to be remarkable. Begun in 520, the dome over the mausoleum was carved out of a single 440-ton slab of limestone and positioned some time between 522 and 526. The low saucer shape of the monolithic dome, which is estimated to be more than 230 tons of Istrian stone, may have been chosen to avoid radial cracking. The twelve brackets carved as part of the dome's exterior are thought to have been used to maneuver the piece into place. The choice of large limestone blocks for the structure is significant as the most common construction material in the West at that time was brick. It is likely that foreign artisans were brought to Ravenna to build the structure; possibly from Syria, where such stonework was used in contemporary buildings.
Kingdom of the Lombards
Duchy of Benevento
The in Benevento was built no later than the 7th century.
Rashidun Caliphate
The Syria and Palestine area has a long tradition of domical architecture, including wooden domes in shapes described as "conoid", or similar to pine cones. When the Arab Muslim forces conquered the region, they employed local craftsmen for their buildings and, by the end of the 7th century, the dome had begun to become an architectural symbol of Islam. The rapidity of this adoption was likely aided by the Arab religious traditions, which predate Islam, of both domed structures to cover the burial places of ancestors and the use of a round tabernacle tent with a dome-like top made of red leather for housing idols.
Visigothic Kingdom
The Chapel of São Frutuoso, near Braga, Portugal, has a wide range of proposed construction dates, from the 7th century to the beginning of the 11th century. It was a Greek cross plan mausoleum with a central dome, similar to the Byzantine Mausoleum of Galla Placidia and the Visigothic churches of and San Pedro de la Nave. The building was restored in the 1930s and the current dome dates to that period, but there are remains of brick pendentives indicating that the original central space was covered by a domical vault of some kind.
The church of Santa María de Melque included a dome within a square structure. Proposed dates for the church have ranged from the 7th to the 10th century, with an 8th-century date indicated by thermoluminescence testing.
Umayyad Caliphate
Umayyad architecture blended elements of multiple traditions, and this is evident in its dome structures. Early versions of bulbous domes can be seen in mosaic illustrations in Syria dating to the Umayyad period.
A domed Umayyad throne hall at Kufa was built on the Sassanian model.
The Dome of the Rock in Jerusalem, the earliest surviving Islamic building, was completed in 691 by Umayyad caliph Abd Al-Malik. Its design was that of a ciborium, or reliquary, such as those common to Byzantine martyria and the major Christian churches of the city. The rotunda of the nearby Church of the Holy Sepulchre, in particular, has a similar design and almost the same dimensions. The building was reportedly burned in the eleventh century and then rebuilt, which would still make it one of the oldest timber buildings in the world. The dome, a double shell design made of wood, is 20.44 meters in diameter. The dome's bulbous shape "probably dates from the eleventh century." Several restorations since 1958 to address structural damage have resulted in the extensive replacement of tiles, mosaics, ceilings, and walls such that "nearly everything that one sees in this marvelous building was put there in the second half of the twentieth century", but without significant change to its original form and structure. It is currently covered in gilded aluminum. On the same terrace are the Dome of the Chain (also from the reign of Abd Al-Malik), the Dome of the Ascension (built by 985 AD), and the Dome of the Spirits (possibly the 16th century AD).
Byzantine workmen built the Umayyad Mosque of Damascus and its hemispherical dome for al Walid in 705. The dome rests upon an octagonal base formed by squinches. The dome, called the "Dome of the Eagle" or "Dome of the Gable", was originally made of wood but nothing remains of it. It is supposed to have rested upon large cross beams.
The placement of a dome in front of the mihrab of a mosque probably began with the rebuilding of the Prophet's Mosque in Medina by Umayyad Caliph Al-Walid. This was likely to emphasize the place of the ruler, although domes would eventually become focal points of decoration and architectural composition or indicate the direction of prayer. Later developments of this feature would include additional domes oriented axially to the mihrab dome.
In addition to religious shrines, domes were used over the audience and throne halls of Umayyad palaces, and as part of porches, pavilions, fountains, towers and the calderia of baths. Blending the architectural features of both the Byzantine and Persian architecture, the domes used both pendentives and squinches and were made in a variety of shapes and materials. Muslim palaces included domical halls as early as the eighth century, well before domes became standard elements of mosque architecture.
The early eighth-century palace of Khirbat al-Minya included a domed gateway.
At Qasr al-Hallabat, the remains of a dome on pendentives show the curves of the pendentives and the supporting arches were carved from the same arch voussoir blocks. Pendentives were normally distinct from and built after their supporting arches.
Although earlier palaces had domes over throne rooms or housed gates in domed structures, the Amman palace is the first to have both. Domes over the entrance to the palace and over the throne room marked the two poles of the complex. The dome over the throne room was supported by "lintelled squinches", a unique example of horizontal stone elements imitating the Partho-Sassanian technique of placing timber beams diagonally over the corners of a square space, creating a smaller square rotated by 45 degrees which would have additional beams over its corners, so that a series of squares were formed in the ceiling inscribed within each other with 45 degree rotations.
The palace of Qasr Mshatta included a domed throne room. At Mshatta, "an elaborate entrance leads through a basilical hall to a domed triconch hall with an arcuated niche, presumably holding the caliphal throne, at the far end." This axial sequence of gateway, dome, and arcuated niche is found in early Islamic palaces into the Abbasid era, and the similar sequence of gateway, dome, and mihrab endured even longer in mosque architecture.
A domed structure covered a shallow pool in the main courtyard of the mid-eighth-century palace of Khirbat al-Mafjar. Similar examples at mosques, such as the domed fountains at the Mosque of Ibn Tulun (destroyed in 987 and replaced with a different structure), at Maarrat al-Numan, in Nishapur, Tripoli, and at the Mosque of Damascus seem to be related to this element of palace architecture, although they were later used as part of ritual ablution. The palace dome was supported by terracotta figures where the pendentives or squinches would have been. The dome was over the porch of a great bath or throne room at the bath complex. The Mafjar bathhouse also had unusual pendentives shaped from a shallow dome and four inclined parabolic arches.
The calderia of early Islamic bath complexes at Amra, Sarraj, and Anjar were roofed with stone or brick domes. The caldarium of the early Islamic bath at Qasr Amra contains "the most completely preserved astronomical cupola decoration", a decorative idea for bath domes that would long continue in the Islamic world. Traces of mosaic decoration have been found on a dome on pendentives at Qusayr 'Amra.
Architecture in the region would decline following the movement of the capital to Iraq under the Abbasids in 750.
Carolingian Empire
In Italy, there seems to have been a decline in the frequency of dome building between the 8th and 10th centuries. With the crowning of Charlemagne as a new Roman Emperor, Byzantine influences were largely replaced in a revival of earlier Western building traditions, but occasional exceptions include examples of early quincunx churches at Milan and near Cassino. The extensive Byzantine use of domes on spherical pendentives after the sixth century did influence Carolingian architecture of the ninth and tenth centuries. Remains of spherical pendentives have been found in the church of Germigny-des-Prés.