MESOPOTAMIA. – Region lying between the mountains (Kāśīrī) of Armenia to the north, the Zagros range to the east, and the Syrian-Arabian desert to the south; to the west it borders on the Taurus and Anti-Lebanon ranges. It may be divided into Upper Mesopotamia, which extends as far as 'Abd el-'Azīz, Singār, and Hamrīn; Middle Mesopotamia, which reaches the borders of Babylonia; and Lower Mesopotamia, which is Babylonia itself, previously known as Akkad (north) and Sumer (south). The name Mesopotamia is generally restricted to Middle and Lower Mesopotamia. Notable are the two great rivers, the Euphrates and the Tigris, which, rising in Armenia, diverge to a maximum distance of about 467 km before converging near Baghdad, then diverging again until they unite to form the Shatt al-'Arab (at al-Qurnah), a river that, after about 161 km, empties into the Persian Gulf. The Jezirah, an island, is the region between the Tigris, the Euphrates, and the Khabur, which, like the Balikh to its west, is a tributary of the Euphrates. In the east, the two rivers Zab and especially the Diyala contribute to the Tigris’s swift and violent course, which is difficult to navigate.
The uniform character of Mesopotamia compelled its inhabitants either to cultivate the fertile soil, thereby forming powerful states (v. MARIA; MITANNI), or to engage in nomadic pastoralism in the areas farthest from the rivers.
Mesopotamia had many names. Already Šamši-Adad I (1748–1716 BC) of Assyria referred to it as “the land between the Tigris and the Euphrates.” The importance of these two rivers is reflected in the name *Nahrina* of el-'Amrnah, *Naharin* of the Egyptians, and *Aram-naharaim* of the Bible, which was used from the 16th to the 10th century BC. For the dual or non-dual explanation of this name and its synonyms, Mitanni, Hani-galbat, Hurri, V. MITANNI. Most Assyrian conquerors mention names of cities in Mesopotamia or localities such as Šubaru, Kummub, Bit-Adini, etc. From the time of Ashurbanipal (669–626 BC) onward, the phrase *ebir nāri*, “beyond the river,” denotes the Assyrian provinces west of the Euphrates, while in Persian texts it refers to the satrapy of Syria, which, under Darius, also included the region east of the Euphrates. The dual force of *Naharaim* is seen in the Greek Μεσοποταμία (in the Septuagint, Codex B of 1 Chron 3:8, 10 reads Συρία ποταμόν instead), which strictly speaking refers to the land between the two great rivers. Usage, however, varied. Alexander the Great, it seems, founded a new satrapy under the name Μεσοποταμία, which extended east of the Tigris, and this satrapy persisted into the Seleucid period. Eratosthenes and Strabo exclude Babylonia from the concept of Mesopotamia, while Pliny sometimes includes II. The Roman province of Mesopotamia, probably existing from AD 193, seems to have extended from the Khabur to the Tigris, and after Diocletian also included the region of Amida in the north. For the history of Mesopotamia, V. AS-SIRI.
Roger T. O'Callaghan
CHRISTIAN ANTIQUITY. – Mesopotamia is the only region in which, during the first centuries of the common era, a major Christian art developed outside not only the political frontiers of the Roman Empire but also—and more importantly—its cultural milieu, without any relation or influence from its artistic expression or, in general, from that late Hellenism of which it was the final survival. It thus represents a unique and highly significant phenomenon. It is understood, however, that reference is always to historically Sasanian Mesopotamia, since two ecclesiastical provinces, though part of the same geographical region, were in quite different conditions: these are Osrhoene, namely the region of Edessa with the monuments of that city and of Wiranēhīr, and Roman Mesopotamia with those of Diyarbakır (Amida) and Mayafaraqin (Martyrpolis), which are connected with those of northern Syria and must therefore be studied separately.
The origins of the Christian evangelization of Mesopotamia are very obscure: Christ’s religion probably first spread among the powerful and wealthy Jewish communities of Babylonia, and of this period one can at most accept the semi-legendary name of Mari and the activity of missionaries from Edessa, aided by the large importation of Roman prisoners, mainly from Celesyria, which was already largely Christian by the 3rd century. By the end of the 3rd century, an ecclesiastical organization was already established, and the see of Seleucia-Ctesiphon was held by Papa bar 'Aggai, the historical founder of the Church of Mesopotamia.
The Christians of Mesopotamia thus soon found themselves, perhaps already in the 2nd century, compelled to construct religious buildings, churches, as is also documented by the *Mithia Zkha* or religious chronicle of Adiabene, whose substantial authenticity has been vainly contested for a very early period.
The most archaic Christian sanctuary known today is that discovered at Qasr bint al-Qadi in Ctesiphon. Excavations have revealed two churches, the second built over the ruins of the first, sharing the same perimeter walls. The lower church is a very elongated rectangular hall with two rows of columns along the longer walls, almost flush against them; the apse has completely disappeared. The structure of this hall closely resembles that of certain royal halls. The second church is much better preserved: it is a rectangular hall with doors only in the long walls; the western wall is completely solid, while the eastern wall has doors leading to three rectangular chambers forming the triple sanctuary characteristic of Mesopotamian churches even in later periods. Along the long walls are two rows of four pillars each, connected to the perimeter walls by arches that likely supported conches. The structure is identical to that of a hall in the Palace of Sarvistan from the time of Bahrām Gūr (420–438). From an examination of these monuments, two fundamental facts emerge: first, the church is conceived as a broad hall, i.e., with entrances on the long sides, thus repeating a very ancient Mesopotamian tradition in temple architecture, in contrast to the classical tradition, which (with very rare exceptions) always placed the entrance on one of the short sides. Second, the church copies in its architectural structure a large hall of a contemporary royal palace. The Christians of Mesopotamia, needing to build a church and living entirely outside any classical tradition that led to the adoption of the basilica form, conceived it according to the most ancient indigenous tradition of the temple as a broad hall and gave it the architectural forms of the great assembly halls of contemporary royal palaces. This constitutes their profound characteristic.
Later periods include the two churches discovered at al-Hīrah. Both have the general form of the churches cited at Ctesifonte, namely that of an elongated rectangle with entrances on the longer sides and with the same triple sanctuary. One of these churches has a nave divided into three parts by two rows of four large round pillars. In the middle of the church, which would be the central nave, there is the Būmaz, that is, an elevated platform above the floor with a bench for the priests on three sides, according to a structure that is found at Rusfāḥ and in very many churches of northern Syria, and which is well described in the liturgical treatise attributed to George of Arbela.
The churches of al-Hīrah are decorated with stuccoes of the dominant style in Mesopotamia in the 7th century. Of a completely different type are the churches found in the northern part of the region, in the Ṭūr ʿAbdīn. The most important are those of Mar ʿAzīz at Kefr Zeḥ, of Mar Kyriakos at Arnās, and of Mar Philoxenus at Midyād. They always have a floor plan of large rectangular halls, very elongated, without interior supports and therefore with a single nave, ending in an apse to the east, surrounded by several rooms, some even behind the apse itself. Generally, they have to the south a rectangular narthex, as long as the church. This is covered with a barrel vault resting on a series of arcades leaning against the long walls. Such a structure is already found in the small Syrian temple of Dār Rās and is characteristic of the great audience halls, the "porticoes" of Muslim palaces: thus at Masāda, Khirbat al-Mafjar, and Ukhayḍir. The conception of taking as a model for the church the great hall of the palace assembly thus continues.
But the Ṭūr ʿAbdīn has also preserved several examples of monastic churches. Monasticism is very ancient in Mesopotamia: tradition connects it with an Awgīn (Eugenius) of Clysma (Suez) who would have imported from his native Egypt the Rules of St. Anthony and St. Pachomius, but certainly the monuments that still remain are much later than the supposed period of this legendary figure. The most important are: that of Qartamīn, which probably dates from the time of Emperor Anastasius (491–518), and those of Mar Ibrāhīm and Mar Ubil at Midyād. The church consists of a narthex in the form of a portico on pillars, from which one enters a rectangular hall covered with a barrel vault, a wide hall where the vault’s generatrices are perpendicular to the axis of the building. The rear wall of the hall is pierced by three doors that give access to the three square chambers of the sanctuary. The walls are lined with large arcades as in the group of churches previously described. At the monastery of Mar Yaʿqūb al-Ḥabīs at Ṣalah, the same church plan is found, with the sole difference that the central chamber of the sanctuary is provided with an apse, semicircular on the inside and polygonal on the outside, of definite Byzantine influence. The characteristic of the triple sanctuary together with the portico in front connects the plan of these churches with the type of the Babylonian temple, especially approaching its Roman-era derivations, such as the Qaṣr Firʿawn at Petra or the temples of the Palmyrene gods and of Artemis-Nanaya at Dūru. More precise Syrian influences are found in the church of al-ʿAdrā at Hāḥ: the carved decoration is entirely of North Syrian type, and the plan of the central hall with the middle part uncovered by a dome and the two ends by two semi-domes, and the central part of the sanctuary, semicircular with the facing decorated by niches interspersed with small columns, brings it close to the monuments of the tricoro cella type of Palestine and Egypt.
In the later Middle Ages, churches of an entirely different form from those so far described are found in Mesopotamia, namely a structure of three elongated naves, separated by two rows of pillars, all covered with barrel vaults at the same height, with the usual triple sanctuary where the chambers are also covered with barrel vaults and exceptionally by domes, as at the Ulu Gami of Karkūḥ, at the churches of Mar Petrōs and that of Mar Ahūdīḥemmech, both at Moqul, and at that of the monastery of Mar Behinām. Other churches, such as those of Mar Girgis, of Mar Yaʿqūb, of Tahrat Mirām al-ʿAdrā, all at Moqul, have a more complex form of sanctuary, different from case to case and not reducible to a fixed rule. There are, however, churches with a single nave, such as that of the monastery of Mar Awgīn or that of Mar Yūḥannān at Moqul. The first of these is a reconstruction from the year 1582 of the Seleucid era (≈ 1271). Notable in these churches is the rich carved decoration, especially at Mar Ahūdīḥemmech, where some decorative elements belong to the time of Nūr al-Dīn and others to the Mongol period; Mar Petrōs with fragments from the time of Badr al-Dīn Luʾluʾ, and the monastery of Mar Behinām rebuilt in 1164. Also noteworthy are the structures of the domes with apparent ribbing executed in the style of star-shaped polygons of the Seljuk type, which are also found in the mosque of Isfahan. All this decoration is absolutely of the same style as that found in contemporary Islamic monuments. The phenomenon of stylistic and iconographic identity of Christian and Muslim artistic productions in Mesopotamia under the Seljuks and the Il-Khans is not limited to architectural decoration. One must also take into account the many objects in bronze and inlaid copper, of which many bear Christian subjects and of which the center of production was mainly Moqul. These are works of artists who worked indifferently for Christians and Muslims, such as the well-known Dāwūd ibn Salamā. The religious tolerance of that period extends to the point that the masterpiece of this series, namely the large dish with Christian subjects now in the collections of the Duke of Arenberg in Brussels, was executed, according to an inscription on it, for Malik Sāliḥ Ayyūb, Sultan of Egypt and Damascus in 1240–49, who was of Mesopotamian origin. The same fusion of the art of the two communities is manifested also in the illuminations: see