Sack of Amorium
The siege of Amorium by the Abbasid Caliphate in mid-August 838 was one of the major events in the long history of the Arab–Byzantine Wars. The Abbasid campaign was led personally by the Caliph al-Mu'tasim, in retaliation to a virtually unopposed expedition launched by the Byzantine emperor Theophilos into the Caliphate's borderlands the previous year. Mu'tasim targeted Amorium, an Eastern Roman city in western Asia Minor, because it was the birthplace of the ruling Byzantine dynasty and, at the time, one of Byzantium's largest and most important cities. The caliph gathered an exceptionally large army, which he divided in two parts, which invaded from the northeast and the south. The northeastern army defeated the Byzantine forces under Theophilos at Anzen, allowing the Abbasids to penetrate deep into Byzantine Asia Minor and converge upon Ancyra, which they found abandoned. After sacking the city, they turned south to Amorium, where they arrived on 1 August. Faced with intrigues at Constantinople and the rebellion of the large Khurramite contingent of his army, Theophilos was unable to aid the city.
Amorium was strongly fortified and garrisoned, but a local inhabitant revealed a weak spot in the wall, where the Abbasids concentrated their attack, effecting a breach. Unable to break through the besieging army, Boiditzes, the commander of the breached section, privately attempted to negotiate with the Caliph without notifying his superiors. He concluded a local truce and left his post, which allowed the Arabs to take advantage, enter the city, and capture it. Amorium was systematically destroyed, never to recover its former prosperity. Many of its inhabitants were slaughtered, and the remainder driven off as slaves. Most of the survivors were released after a truce in 841, but prominent officials were taken to the caliph's capital of Samarra and executed years later after refusing to convert to Islam, becoming known as the 42 Martyrs of Amorium.
The conquest of Amorium was not only a major military disaster and a heavy personal blow for Theophilos, but also a traumatic event for the Byzantines, its impact resonating in later literature. The siege did not ultimately alter the balance of power, which was slowly shifting in Byzantium's favour, but it thoroughly discredited the theological doctrine of Iconoclasm, ardently supported by Theophilos. As Iconoclasm relied heavily on military success for its legitimization, the fall of Amorium contributed decisively to its abandonment shortly after Theophilos's death in 842.
Background
By 829, when the young emperor Theophilos ascended the Byzantine throne, the Byzantines and Arabs had been fighting on and off for almost two centuries. At this time, Arab attacks resumed both in the east, where after almost twenty years of peace due to the Abbasid civil war, Caliph al-Ma'mun launched several large-scale raids, and in the west, where the gradual Muslim conquest of Sicily was under way since 827. Theophilos was an ambitious man and also a convinced adherent of Byzantine Iconoclasm, which prohibited the depiction of divine figures and the veneration of icons. He sought to bolster his regime and support his religious policies by military success against the Abbasid Caliphate, the Empire's major antagonist.File:Theophilus follis.jpg|thumb|upright=1.2|right|alt=Image of bronze coin, a standing crowned man holding a labarum and a globus cruciger on the obverse, with a Greek-Latin inscription on the reverse|Follis of a new type, minted in large quantities in celebration of Theophilos's victories against the Arabs from ca. 835 on. On the obverse, he is represented in triumphal attire, wearing the toupha, and on the reverse the traditional acclamation "Theophilos Augustus, you conquer".
Seeking divine favour, and responding to iconophile plots against him, Theophilos reinstated active suppression of the iconophiles and other perceived "heretics" in June 833, including mass arrests and exiles, beatings and confiscations of property. In Byzantine eyes, God seemed indeed to reward this decision: al-Ma'mun died during the first stages of a new, large-scale invasion against Byzantium that was intended to be the first step in conquering Constantinople itself, and his brother and successor al-Mu'tasim withdrew to focus on internal matters, having trouble establishing his authority, and needing to confront the ongoing rebellion of the Khurramite religious sect under Babak Khorramdin. This allowed Theophilos to achieve a series of modest victories over the next few years, as well as to bolster his forces with some 14,000 Khurramite refugees under their leader Nasr, who was baptized a Christian and took the name Theophobos. The emperor's successes were not particularly spectacular, but coming after two decades of defeats and civil war under iconophile emperors, Theophilos felt justified in claiming them as vindication for his religious policy. Consequently, the emperor began to publicly associate himself with the memory of the militarily successful and fanatically iconoclast emperor Constantine V, and issued a new type of the copper follis coin, minted in huge numbers, which portrayed him as the archetypical victorious Roman emperor.
In 837, Theophilos decided—at the urging of the hard-pressed Babak—to take advantage of the Caliphate's preoccupation with the suppression of the Khurramite revolt and lead a major campaign against the frontier emirates. He assembled a very large army, some 70,000 fighting men and 100,000 in total according to al-Tabari, and invaded Arab territory around the upper Euphrates almost unopposed. The Byzantines took the towns of Sozopetra and Arsamosata, ravaged and plundered the countryside, extracted ransom from several cities in exchange for not attacking them, and defeated a number of smaller Arab forces. While Theophilos returned home to celebrate a triumph and be acclaimed in the Hippodrome of Constantinople as the "incomparable champion", the refugees from Sozopetra began arriving at Mu'tasim's capital, Samarra. The caliphal court was outraged by the brutality and brazenness of the raids: not only had the Byzantines acted in open collusion with the Khurramite rebels, but during the sack of Sozopetra—which some sources claim as Mu'tasim's own birthplace—all male prisoners were executed and the rest sold into slavery, and some captive women were raped by Theophilos's Khurramites. Theophilos's campaign was unable, however, to save Babak and his followers, who in late 837 were forced from their mountain strongholds by the general Afshin. Babak fled to Armenia, but was betrayed to the Abbasids and died of torture.
With the Khurramite threat over, the caliph began marshalling his forces for a reprisal campaign against Byzantium. A huge Arab army gathered at Tarsus; according to the most reliable account, that of Michael the Syrian, it numbered some 80,000 men with 30,000 servants and camp followers and 70,000 pack animals. Other writers give far larger numbers, ranging from 200,000 to 500,000 according to al-Mas'udi. Unlike earlier campaigns, which did not go far beyond attacking the forts of the frontier zone, this expedition was intended to penetrate deep into Asia Minor and exact vengeance. The great city of Amorium in particular was the intended prize. The Arab chronicles record that Mu'tasim asked his advisors to name the "most inaccessible and strongest" Byzantine fortress, and they named Amorium, "where no Muslim has gone since the appearance of Islam. It is the eye and foundation of Christendom; among the Byzantines, it is more famous than Constantinople". According to Byzantine sources, the caliph had the city's name written on the shields and banners of his soldiers. The capital of the powerful Anatolic Theme, the city was strategically located at the western edge of the Anatolian plateau and controlled the main southern route followed by the Arab invasions. At the time, Amorium was one of the largest cities in the Byzantine Empire, ranking in importance immediately after Constantinople. It was also the birthplace of Theophilos's father, Michael II the Amorian, and perhaps of Theophilos himself. Due to its strategic importance, the city had been a frequent target of Arab attacks in the 7th and 8th centuries, and Mu'tasim's predecessor Ma'mun was said to be planning to attack the city when he died in 833.
Opening stages of the campaign: Anzen and Ancyra
The Caliph's Amorium campaign followed immediately after the defeat and execution of Babak. The Amorium campaign against the Byzantines was led by the caliph himself. The caliph divided his force in two: a detachment of 10,000 horse-archers under Afshin was sent northeast to join forces with the emir of Malatya Umar al-Aqta and Armenian troops and invade the Armeniac Theme from the Pass of Hadath, while the main army under the caliph himself would invade Cappadocia through the Cilician Gates. The advance guard of the latter was led by Ashinas, with Itakh commanding the right, Ja'far ibn Dinar al-Khayyat the left, and 'Ujayf ibn 'Anbasa the centre. The two forces would link up at Ancyra, before marching jointly on Amorium. On the Byzantine side, Theophilos was soon made aware of the caliph's intentions, and set out from Constantinople in early June. His army included men from the Anatolian and possibly also the European themes, the elite tagmata regiments, as well as the Khurramites. The Byzantines expected the Arab army to advance north to Ancyra after passing through the Cilician Gates and then to turn south toward Amorium, but it was also possible that the Arabs would march directly over the Cappadocian plain to Amorium. Although his generals advised evacuation of the city, with the intention of rendering the Arabs' campaign objective void and keeping the Byzantine army undivided, Theophilos decided to reinforce the city's garrison, with Aetios the strategos of the Anatolics, and men from the tagmata of the Excubitors and the Vigla.With the rest of his army, Theophilos then marched to interpose himself between the Cilician Gates and Ancyra, camping on the north bank of the River Halys, close to one of the major river crossings. Ashinas crossed the Cilician Gates on 19 June, and the caliph himself with his main army set out on the march two days later. The Arab advance was slow and cautious. Anxious to avoid an ambush and learn the emperor's whereabouts, Mu'tasim forbade Ashinas to advance too deeply into Cappadocia. Ashinas sent out many scouting detachments to take captives, and from them finally learned of Theophilos's presence at the Halys, where he awaited the Arab approach to give battle. At the same time, around mid-July, Theophilos learned of the arrival of Afshin's army, comprising some 30,000 men, at the plain of Dazimon. Leaving a part of his army under a relative to watch the crossings of the Halys, Theophilos immediately departed with most of his army, some 40,000 men according to Michael the Syrian, to confront the smaller Arab force. Mu'tasim learned of Theophilos's departure from captives and tried to warn Afshin, but the emperor was faster and met Afshin's army in the Battle of Anzen on the plain of Dazimon on 22 July. Despite initial success, the Byzantine army broke and scattered, while Theophilos with his guard were encircled and barely managed to break through and escape.
File:MadridSkylitzesTheophilosArmyFol54r.jpg|thumb|right|upright=1.2|alt=People on horseback riding towards a mountain, the central figure is clad in gold cuirass and crown|Emperor Theophilos flees after the Battle of Anzen, miniature from the Madrid Skylitzes manuscript.
Theophilos quickly began regrouping his forces and sent the general Theodore Krateros to Ancyra. Krateros found the city completely deserted, and was ordered to reinforce the garrison of Amorium instead. Theophilos himself was soon forced to return to Constantinople, where rumours of his death at Anzen had led to plots to declare a new emperor. At the same time, the Khurramites, gathered around Sinope, revolted, and declared their reluctant commander Theophobos emperor. Luckily for the Empire, Theophobos maintained a passive stance and made no move to confront Theophilos or join Mu'tasim. The caliph's vanguard under Ashinas reached Ancyra on 26 July. The inhabitants, who had sought refuge in some mines nearby, were discovered and taken captive after a brief struggle by an Arab detachment under Malik ibn Kaydar al-Safadi. The Byzantines, some of whom were soldiers who had fled from Anzen, informed the Arabs of Afshin's victory, after which Malik allowed all of them to go free. The other Arab forces arrived at Ancyra over the next days, and after plundering the deserted city, the united Arab army turned south towards Amorium.