Al-'Awasim

The al-'Awāṣim (العواصم, "defences, fortifications"; sing. al-'āṣimah, "protectress") was the Arabic term used to refer to the Muslim side of the frontier zone between the Byzantine Empire and the Umayyad and Abbasid Caliphates in Cilicia, northern Syria and Upper Mesopotamia. It was established in the early 8th century, once the first wave of the Muslim conquests ebbed, and lasted until the mid-10th century, when it was overrun by the Byzantine advance. It comprised the forward marches, comprising a chain of fortified strongholds, known as the al-thughūr (الثغور; sing. الثغر, al-thagr, "cleft, opening"), and the rear or inner regions of the frontier zone, which was known as the al-'awāṣim proper. On the Byzantine side, the Muslim marches were mirrored by the institution of the kleisourai districts and the akritai border guards.

The term thughūr was also used in the marches of al-Andalus and Mawara al-Nahr, and survived in historical parlance, to be revived by the Egyptian Mamluks in the 14th century, when the areas traditionally comprising the 'awāṣim and thughūr in northern Syria and the northern Euphrates region came under their control.

Creation of the frontier zone
Already from late 630s, after the rapid Muslim conquest of Syria, a wide zone, unclaimed by either Byzantines or Arabs and virtually deserted (known in Arabic as al-Ḍawāḥī, "the outer lands" and in Greek as τὰ ἄκρα, ta akra, "the extremities") emerged between the two powers in Cilicia, along the southern approaches of the Taurus and Anti-Taurus mountain ranges, leaving the Anatolian plateau in Byzantine hands. Both Emperor Heraclius (r. 610–641) and the Caliph 'Umar (r. 634–644) pursued a strategy of destruction within this zone, trying to transform it into an effective barrier between their realms. Nevertheless, the ultimate aim of the caliphs remained the outright conquest of Byzantium, as they had done with its provinces in Syria, Egypt and North Africa, and it was only the failure of the Second Arab Siege of Constantinople in 717–718 that forced a revision of this strategic objective: although raids into Anatolia continued, the goal of conquest was abandoned, and the border between the two powers began to acquire more or less permanent features. For the next two centuries, border fortresses might change hands between Byzantines and Arabs, but the basic outline of the Arab–Byzantine border remained essentially unaltered. Thus the term al-thughūr, which initially meant "fissures, clefts" (cf. their Greek name τὰ Στόμια, ta Stomia, "the mouths/openings") and designated the actual borderlands, came to mean "boundaries", employed in phrases like Thughūr al-Islām, "boundary of Islam" or Thughūr al-Rūmīya, "boundary of the Romans".

This process was marked by a gradual consolidation of the previously deserted zone and its transformation into a settled and fortified borderland, especially after the Byzantines abandoned Cilicia during the reign of Caliph Abd al-Malik (r. 685–705). The Muslims began to move into the area, reoccupying and repairing the abandoned towns and forts. The process began under the Umayyads, but intensified under the first Abbasids, especially during the rule of Harun al-Rashid (r. 786–809). Thus a line of forts was gradually established, stretching from Tarsus (Ar. Ṭarsūs) on the Mediterranean coast to Malatya (Ar. Malaṭiyā, Gr. Melitene) and Kamacha (Ar. Ḥiṣn Kamkh) on the upper course of the Euphrates. These were located at strategic choke points, located at the intersections of major roads or at the mouths of important passes.

Administrative organization and settlements
The entire frontier zone was initially part of the jund (one of the military administrative divisions into which Muslim Syria was divided) of Homs. After 680 it formed part of the new jund of Qinnasrin (Gr. Chalkis), until Harun al-Rashid established a separate jund al-'Awāṣim in 786, covering the entire region from the Byzantine border in the north and west to the Euphrates in the east and a line running south of Antioch (Ar. Anṭākiya), Aleppo (Ar. Ḥalab, Gr. Berroia) and Manbij (Gr. Hierapolis). Manbij and later Antioch were the new province's capitals. The al-'Awāṣim proper served as the second defensive line behind the Thughūr, stretching across northern Syria and comprising the towns of Baghras, Bayās, Dulūk (Gr. Doliche or Telouch, modern Gaziantep), Alexandretta (Ar. Iskandarīya), Cyrrhus (Ar. Ķūrus), Ra'bān and Tīzīn. The Thughūr, the actual frontier zone, was divided into the Syrian (Thughūr al-Sha'mīya) and the Upper Mesopotamian (Thughūr al-Jazīrīya) sectors, roughly separated by the Amanus mountains. There was no overall governor or a capital, although Tarsus and Malatya were the most important towns in Cilicia and the Mesopotamian sector respectively. The towns of the Thughūr came variously under the administrative control of the jund al-'Awāṣim or functioned as separate districts. The situation is complicated by the fact that by the 10th century, the terms Thughūr and al-'Awāṣim were often used interchangeably. In addition, from the early 10th century, with the Byzantine advance into Armenia, the frontier around Diyār Bakr became a third sector, Thughūr al-Bakrīya.

In the Cilician sector, Mopsuestia (Ar. al-Maṣṣīṣa) was the first city to be re-occupied and garrisoned, already under the Umayyads, who settled 300 soldiers there in 703, a number raised under the first Abbasids to some 4,000. Adana followed in 758–760, and Tarsus in 787/788. Tarsus quickly became the largest settlement in the region and the Arabs' most important base of operations against the Byzantines, counting between 4,000 and 5,000 troops in its garrison. Other important fortresses in Cilicia, which however were little more than military outposts, were 'Ayn Zarba (Gr. Anazarbus), al-Hārūniya, founded by Harun al-Rashid, Tall Gubair and al-Kanīsat al-Sawdā. These were complemented by smaller forts dotted across the Cilician plain, holding smaller garrisons of a dozen or so men. In the more mountainous terrain of the Upper Mesopotamian frontier zone, the main strongholds were located in the fertile parts of relatively isolated valleys, controlling the entrances of passes over the mountains: Mar'ash (Gr. Germanikeia), rebuilt already under Muawiyah I (r. 661–680) and again under Harun al-Rashid, al-Ḥadath (Gr. Adata), likewise refortified by the first Abbasid caliphs and provided with 4,000 troops, and Malatya, which had been colonized by the Umayyads, destroyed by the Byzantines and rebuilt again and likewise garrisoned with 4,000 men in 757/758. Further fortresses of lesser importance in the Mesopotamian sector were Salaghus, Kaisum, Ḥiṣn Zibaṭra (Gr. Zapetra/Sozopetra), Sumaisaṭ (Gr. Samosata), Ḥiṣn Qalawdhiya and Ḥiṣn Ziyad. Some of the northern fortresses of the al-'Awāṣim province, like Dulūk or Cyrrhus, were also sometimes included in it. Further north, the relatively isolated fortress towns of Qālīqalā (Gr. Theodosiopolis, modern Erzurum) and Kamacha formed the northern-most outposts of Muslim rule. The Thughūr al-Bakrīya included, according to Qudama ibn Ja'far, Sumaisaṭ, Ḥānī, Malikyan, Gamah, Ḥaurān and al-Kilis.

The caliphs repopulated the area by bringing in colonists and regular soldiers from Syria but also Persians, Slavs, Arab Christians, and people from the eastern edges of the Muslim world: settlers from Khurasan, the Turkic Sayābija tribe or Jatts (Ar. Zuṭṭ) from India. The regular troops stationed there were favoured with lower taxes (the tithe or 'ushr instead of the kharāj land tax), higher pay and small land grants (qaṭā'i). In early Abbasid times these troops numbered some 25,000, half of them drawn from Khurasan and the rest from Syria and Upper Mesopotamia. They were complemented by volunteers, drawn by the religious motivation of jihad against the Byzantines but often paid a salary by the state as well. All this entailed a heavy financial burden on the Abbasid state. Under Harun al-Rashid, taxation from the Cilician sector brought in 100,000 gold dinars, which were all spent for public works, salaries, espionage etc. In addition, the costs of cross-border expeditions typically ranged between 200,000–300,000 dinars. The Mesopotamian sector's revenue amounted to some 70,000 dinars, to which the central government added 120,000–170,000 dinars each year for the upkeep of the fortifications and the salary of the frontier troops.

Military operations
By the 9th century, the Arab raiding expeditions launched against Byzantium from the frontier zone had gradually assumed an almost ritual character and were strictly organized. According to Qudama ibn Ja'far, the conventional pattern of Arab incursions included a first expedition in spring (10 May–10 June), when horses could find abundant fodder, followed after about a month's rest by a summer raid (10 July–8 September), usually the main campaign of the year, and sometimes by a winter raid in February–March. The importance of these raids is summarized by Islamic scholar Hugh N. Kennedy: "the ṣā’ifa (summer raid) was as much a part of the symbolic and ritual functions of the Caliph as was organising and providing leadership for the annual hajj to Mecca".

The frontier zone was fiercely contested between the Arabs and the Byzantines. Raids and counter-raids were a permanent fixture of this type of warfare. Forts on either side of the notional frontier were captured and razed, or sometimes occupied, but never for long. As a result, the region was often depopulated, necessitating repeated resettlement. There is nevertheless evidence of some prosperity, based on agriculture and commerce, especially during the second half of the 9th century, when the borderlands became a node in a commercial route linking Basra with northern Syria and even Constantinople. As the 9th century progressed, the Abbasids' control over the Thughūr devolved to semi-independent border emirates, chiefly Tarsus, Malatya and Qālīqalā. After 842, with the decline of Abbasid power, they were left largely to fend on their own against a resurgent Byzantium. The Battle of Lalakaon in 863 broke the power of Malatya, altering the balance of power in the region, and began a gradual Byzantine encroachment on the Arab borderlands.

With the onset of a prolonged period of crisis in the Abbasid Caliphate after 928, control of the Muslim frontier cities shifted to the Ikhshidid and Hamdanid dynasties. Under the leadership of John Kourkouas, the Byzantines broke through and conquered Malatya and most of the Mesopotamian sector of the Thughūr in the 930s. Although the Hamdanid emir of Aleppo, Sayf al-Dawla (r. 946–967) managed to stem the tide, his success was only temporary: in 964–965, the Emperor Nikephoros II Phokas (r. 963–969) captured Cilicia, followed soon after by Antioch, while Aleppo became a tributary state.

Mamluk–Turkmen frontier zone
After their conquest of Syria, the Egyptian Mamluks re-established the al-thughūr wa-l-'awāṣim as a defensive zone to shield Syria from the Turkoman states of Asia Minor and the Caucasus, including at a later stage the Ottoman Empire. Like the earlier model, the thughūr were divided into a Syrian and a Mesopotamian march, as well as a rear zone along northern Syria. The Mamluks entrusted the defence of the Syrian/Cilician march to the client Turkmen principality of the Ramadanids, while the Dulkadirid principality fulfilled the same role in the Mesopotamian thughūr. To safeguard their control of the frontier zone, and to keep the two client beyliks separated and under control, the Mamluks also retained garrisons in seven strategically important sites: Tarsus, Ayas, Serfendikar, Sis, Darende, Malatya and Divriği. Ahmad al-Qalqashandi gives the subdivisions (niyābāt) of the Mamluk thughūr as follows: eight for the Syrian sector (Malatya, Divriği, Darende, Elbistan, Ayas, Tarsus and Adana, Serfendikar and Sis) and three on the Euphrates sector (al-Bira, Qal'at Ja'bar and al-Ruha).