The first wave of Muslim Arab conquests rapidly thrust aside the armies of both the Byzantine and Sassanian empires to reach areas immediately south of the Caucasus, and in 640 Arab forces invaded Armenia. Nearby, the Khazars had dominated Azerbaijan since 632, so the sudden approach of the victorious Arabs caused them to seek allies. The first recorded clash between Muslims and Khazars was in 642, when Arab raiders reached Derbent at the narrowest point between the Caucasus mountains and the Caspian coast. The following year the Muslims pushed beyond Derbent, towards the Khazars’ then-capital at Balanjar; meanwhile, in Armenia, in 645–646 the Caliph’s army defeated a Byzantine force which included both Khazar and Alan allies. Seven years later a Muslim army of conquest complete with siege engines attacked Balanjar, but in the resulting battle the Khazars reportedly also used siege weapons and ballistas, killing the Muslim commander and driving back his army.
Turmoil within the Islamic world now enabled several frontier areas to regain virtual independence, including Armenia, Georgia, and Azerbaijan. However, the establishment of the Umayyad Caliphate in 661 resulted in the creation of a huge, stable, remarkably efficient and militarily effective state centred in Syria. Although the Islamic conquests resumed, the Khazars also remained powerful and expansionist, striking south of the Caucasus in 684. This was apparently in response to the actions of Alp, the Christian Ilutuer or vassal ruler of the Khuni people of the northern Caucasus (who may themselves have been a relic of the Hun Empire which had collapsed more than two centuries earlier). Alp’s raiding of Khazar territory provoked retaliation which devastated several areas and killed several local rulers; the Khazars also levied a heavy tribute.
Much of Armenia was nevertheless now under Muslim suzerainty, and in 692 the caliph’s governor, Muhammed ibn Marwan, retook Derbent and tried to establish a strong frontier zone against future Khazar aggression. This strategic region changed hands several times, while both sides also watched with interest the political turmoil in the Byzantine Empire. In 713, Habib ibn Maslama forced back an invading Khazar army with difficulty, but then regained Derbent after a three-month siege◦– though only when a local citizen betrayed a subterranean passage into the fortress. Believing Derbent to be indefensible with his available forces, Habib ordered its fortifications razed before pushing north deeper into Khazar territory. He reached Samander (now Tarku), where the Khazar army made a stand. For several days champions from each side duelled in the space between the two armies before Habib, recognizing his numerical inferiority, abandoned his baggage train, and led his army back to Georgia while the Khazars were preoccupied with looting the Muslims’ abandoned camp.
In 721 the Khazars took the offensive, invading Armenia and destroying Muslim garrisons. This was followed by 15 years of warfare, during which the Caliphate’s still largely Arab forces were often greatly outnumbered but generally more sophisticated. They were superior in technology, tactics, and political strategy (for example, attempting to win over local inhabitants while expelling Khazar garrisons). On one occasion the Muslim commander Jarrah ibn Abdallah took Samandar, then turned south again towards Balanjar. In an attempt to bar his passage the Khazar garrison used an old form of field fortification long traditional amongst steppe nomads, constructing a camp surrounded by wagons and carts tied together. However, Muslim soldiers advanced to this perimeter under the cover of arrows (probably shot by Arab infantry), cut the ropes and broke through the Khazars’ barrier. After brutal hand-to-hand combat, the ‘prince’ (governor) of Balanjar and 50 of his men escaped, while leaving the Khazar leader’s family to be captured. Jarrah ibn Abdallah now sent another senior captive after the Khazar commander, promising that he could continue ruling Balanjar under Muslim suzerainty. Following this successful campaign, in which both Balanjar and Samandar cities were left intact in return for payment of tribute, each Arab cavalryman was rewarded with 300 dinars from the booty, while infantrymen got 100 each; one-fifth of the total loot was also set aside for the caliph’s government. Jarrah wanted to continue the campaign but, with cold weather approaching, and having been warned that another Khazar army was assembling, he took his troops back to winter quarters in Azerbaijan. As so often happened in this part of the world, ‘General Winter’ had intervened to force back an invader.
In 730, encouraged by recent successes, the Khazars invaded Islamic territory. They were commanded by Barjik, whom Arab chroniclers described as ‘son of the Khagan’, though he may already have been the ruler. Bursting into Azerbaijan, he ordered his troops to slaughter Muslims wherever they were found, and led the main Khazar force towards Ardebil. Here, outside the city walls, the veteran Jarrah ibn Abdallah was defeated and slain; Ardebil then fell, after which Khazars spread across the country to loot and pillage. However, Said ibn Amr al-Harashi was now in command of Muslim forces, and, perhaps having learned from previous failures, he began to destroy the scattered Khazar detachments one by one. Eventually the two main armies came together on the Mugan steppe of north-western Iran. The Arabs were victorious; they overran the Khazar camp, regained lost booty, and almost captured Barjik himself.
Thereafter the war ground on with successes and failures on both sides, until a new Muslim commander, Maslama, decided that strategically vital Derbent must never be lost again. He strengthened its fortifications, established a military arsenal, and brought in a colony of Syrian troops with their families to garrison the citadel. Confident that no more could be done, Maslama handed over command to Marwan ibn Muhammad, a cousin of the caliph (who would later himself become the last Umayyad Caliph of Damascus as Marwan II). In 735, when Marwan offered to make peace, the Khagan sent an ambassador, but negotations turned sour. The Khazar ambassador was seized, and Marwan assembled an army reputedly numbering 150,000 men, including an Armenian detachment led by Prince Ashot. The size of this army enabled Marwan to divide his forces and invade Khazaria by two different routes.
Once he was deep inside Khazar territory, Marwan released the captive ambassador and sent him to the Khagan. The Khazar ruler fell back to a place the Arab chroniclers called al-Baida (‘the White’), which was probably part of the new Khazar capital of Atil. There he left an army, while he raised troops from regions of the Khaganate which had been untouched by the Islamic invasions. Instead of besieging al-Baida, Marwan led his army inland up the right bank of the Volga, eventually ravaging the distant lands of the Burtas, subjects of the Khazars on the northern frontier of the Khaganate. By now the Khagan had returned to shadow the Muslim army from the left bank of the Volga. So Marwan crossed the mighty river by night, using a pontoon bridge or bridges, probably where the river was divided by one or more islands◦– a remarkable feat of military engineering for the 8th century. A group of Arab scouts then killed a Khazar commander in a skirmish, after which Marwan’s army surprised the main Khazar force encamped. The Khazar Tarkhan or senior commander was killed during bitter fighting in which 7,000 Khazar soldiers were reportedly slain, with some 10,000 captured. The Khagan now sued for peace, but Marwan demanded that he convert to Islam. The Khazar leader agreed and◦– briefly◦– did become a Muslim, while also moving his capital to less vulnerable Atil on the Volga Delta.
Marwan ibn Muhammad’s remarkable campaign seemed to mark the triumph of Islam on this front. However, the Umayyad Caliphate was facing serious difficulties closer to home. Marwan ruled as the last Umayyad caliph from 744 to 750, but was then killed and his regime replaced by the new Abbasid Caliphate centred in Iraq. This tumult in the Islamic heartlands enabled the Khazars to rebuild their power, and in 764 a Khazar commander known as Ras Tarkhan invaded Azerbaijan and eastern Georgia within what was now the Abbasid Empire.
Thereafter relations between Khazar Khagans and Abbasid Caliphs remained stable and, after a century of intermittent warfare, the struggle seemed to have ended in a draw. Nevertheless, the Khazar Khaganate had halted the spread of Islam into South-Eastern Europe, providing time and space for Russia to become Christian. The Khaganate had also sometimes served as a valuable strategic ally of the Byzantine Empire during its struggle for survival.
Despite facing a common foe in the Umayyad and subsequently Abbasid Caliphates, the Khazar Khaganate and Byzantine Empire had their own disputes. One episode saw the Khazars supporting King Leon II of Abkhazia (767–768 and 811–812), whose mother was a daughter of the Khazar Khagan, in a successful bid to free himself from Byzantine overlordship and apparently exchange it for Khazar suzerainty.
A more important arena of rivalry was the Crimean peninsula, which, although inhabited by Christians, was largely under Khazar rule. Tensions became acute in 787 when an uprising broke out in Gothia, a Goth principality in south-western Crimea. This relic of earlier Germanic rule was under Khazar suzerainty, and a local Christian bishop named John put himself at the head of the rebellion. A Khazar garrison was expelled from the regional capital of Doros (now Mangup), and the rebels seized control of mountain passes controlling access to the coast. Unwilling to accept this situation, the Khazar Khagan speedily regained Doros, capturing but not executing Bishop John. Since the Khaganate was then a powerful state, the Byzantines who controlled part of the Crimean coast chose not to intervene immediately.
At the start of the 9th century Byzantium took advantage of a civil war in Khazaria between the Khazars and their Magyar vassals, and overran Crimean Gothia apparently with almost no resistance◦– perhaps one of the competing forces within the Khaganate wanted Byzantine support. What seems certain is that Khagan Obadiah was so preoccupied with problems at home that he let Gothia go.
It may have been during the reign of the Khagan Benjamin, in the first years of the 10th century, that the Byzantine Empire took the offensive against Khazaria. For this enterprise the Byzantines found allies amongst other peoples who had quarrels with the Khazars, including the Burtas, Magyars, Central Asian Turks, Ghuzz, Black Bulgars, Pechenegs and perhaps Ossetians. Acting in concert, this loose alliance put the Khazars under huge military pressure, while the Khaganate’s only effective allies seem to have been the Alans. Nevertheless, this first major Khazar-Byzantine war ended in Khazar victory.
The Khagan Aaron II (920s–940) also faced conflict with the Byzantine Empire when, encouraged by the latter, the Alans turned against their erstwhile Khazar allies. By this time the Alans had largely been driven from the north Caucasus plains into the mountains, but they nevertheless remained a formidable force, capable (according to the near-contemporary Muslim chronicler al-Mas’udi) of fielding 30,000 horsemen. In response to their attacks Aaron allied with ‘Twrqy’ or Turks, perhaps meaning the Ghuzz. The Alans were defeated and their ruler captured; Aaron not only treated his prisoner with respect, but married his son Joseph, a future Khagan, to the captured ruler’s daughter◦– the traditional method for cementing an alliance. The Alans are also said to have abandoned their recently accepted Othodox Christian religion in 932, expelling the Byzantine bishop; some Alans now converted to Judaism, though most soon returned to the Orthodox fold.
The Varangian founders of the Kievan Rus state were Scandinavians, largely from Sweden, who had subdued many Slav tribes. The early Varangian aristocracy had followed the example of these peoples in paying tribute to the Khazars, and had even fought for them against the Khaganate’s enemies around the southern Caspian Sea. However, tension between the Rus and Khazars erupted into violence after 914, when Rus returning to the Volga from a Caspian campaign were attacked by the Khazar army’s elite Muslim mercenaries, the Arsiya, and also by Burtas and Volga Bulgar vassals of the Khaganate (see also below, ‘Russian-Khazarian Wars’).
There was significant persecution of Jewish minorities in the Byzantine Empire under Emperor Romanos I (920–944), along with a generally anti-Khazar policy. In response the Jewish Khagan Joseph turned against the many Christians living in Khazaria, and in 939 this resulted in a war during which the Rus sided with the Byzantines. The so-called ‘Helga, king of the Rus’ (either Oleg or Igor of Kiev) suddenly seized the Khazar fortress of Samkertz on the Taman pensinula, overlooking the Kerch straits between the Sea of Azov and the Black Sea. One account claims that no Khazar chief (hapaqid or reb hashmonaya) or garrison was installed there at the time. Another version states that when Samkertz’s garrison commander or governor (bulshitsi), named Pesakh, heard the news he quickly retook this strongpoint. Yet a third version describes Pesakh as the Khazar archon (a Byzantine term for governor) of the Bosphorus, meaning the southern coastal region of the Sea of Azov. According to this account, Pesakh crossed from the Taman peninsula to Crimea, capturing three Byzantine towns and numerous villages before besieging Kherson, which he forced to pay tribute. Having defeated Byzantine forces in the Crimean peninsula Pesakh attacked the Rus in a four-month campaign, regained booty from Samkertz, and defeated ‘Helga’, who now agreed to join forces with the Khazars.
In 941 a large joint Rus and Khazar fleet attacked the imperial capital, Constantinople. This assault, well recorded in Byzantine sources, saw the Rus-Khazar fleet rampaging around the Sea of Marmara and the Black and Aegean Seas. Eventually the Byzantine navy managed to defeat their foes with the aid of their legendary ‘Greek fire’ weapon, after which the Khazars and Rus were also defeated on land.
Despite this failure, ‘Helga’ remained an ally of the Khazars, and in 943 the Khagan sent him to conquer what is now Azerbaijan. The primary target of this enterprise, which served mainly Khazar rather than Rus interests, was a frontier zone of the Islamic Caliphate beyond the vital fortress of Derbent, which the Arabs called ‘the Gate of Gates’. According to Gregory Bar Hebraeus, writing in the 13th century, other Khazar vassals also took part, including Lezgins and Alans from the Caucasus in addition to the usual vassal Slavs.
The subordination of Kievan Rus to the Khazars which had been achieved by Pesakh’s campaign proved relatively short-lived. By the 950s and 960s the Khagan Joseph was again at war with the Rus, to deny them access to the Caspian Sea. His efforts failed; the Rus formed an alliance with the Turkish Ghuzz, and in 964–965 Prince Svyatoslav Igorevich defeated the Khazar Khaganate. Whether the Byzantines also took part in this campaign is unknown, but in 1016 Byzantium and Rus jointly suppressed a rebellion in Crimea by George Tsulo◦– the strategikon of Kherson, who was of Khazar origin. However, this was not a war against Jewish Khazaria, which no longer existed; George Tsulo was himself a Christian.
An ancient Russian chronicle called The Story of Previous Times states that, after the deaths of the legendary founders of Kiev◦– the Slav brothers Kyi, Shchek and Khoryv, and their sister Lybid◦– until 852 the local Slav tribe continued to pay tribute to the Khazars in the form of swords. The historian L.N. Gumilev points out that a tribute of swords was merely the disarming of a people defeated in war by the Khazars, whereas other tribute in furs and silver were valuable trading items. The Varangians who subsequently dominated these Slav tribes similarly demanded such tribute.
Gumilev maintains that it was this diversion of Slav tribute from the Khazars to the newly arrived Scandinavians that led to war between the Khazars and the Varangian Rus, in which the Varangians initially came off worse. However, most experts suggest that a mutually beneficial trade arrangement was concluded between the Rus and Khazars, with Varangian raiders either purchasing or capturing Slavs and Finns to be sold as slaves in Khazaria, most of them destined for ultimate resale in the Byzantine Empire or Islamic territories.
Meanwhile, longer-distance trade, especially in slaves, was virtually monopolized by the Radhonites (Hebrew Radhani, Arabic Radaniyya)◦– Jewish merchants who operated across much of Europe, the Middle East, Central Asia and North Africa from the 6th to 10th centuries AD. What influence Radhonite merchants and their trade might have had on the decision of the Khazar ruling elite to convert to Judaism after about 730 is unknown.
An alliance with the Varangians proved more profitable for the Khazars than exacting tribute directly from the Slav tribes. Furthermore, the Khazar rulers persuaded the fearsome Varangians to take part in campaigns against the peoples of the southern Caspian, whence the main Islamic threat to the Khaganate originated. During the late 9th and early 10th centuries such raids could prove highly profitable for both participants when, as described by the Muslim chronicler al-Mas’udi, they shared the booty. This relationship often sounds like one between equal allies, or perhaps just between mercenaries and those who hired them.
The first significant war between the Varangian Rus and Khazaria took place around 913–914 when, again according to al-Mas’udi, a Rus fleet of some 500 ships, each containing 40–100 warriors, appeared in the Kerch Strait. There they asked the Khazar authorities for permission to sail up the Don, to travel across the famous portage near today’s Volgograd (ex-Stalingrad), then down the Volga to the Caspian, and permission was granted in return for an eventual share of their anticipated booty. The Rus entered the Caspian and raided various Muslim territories, including Gilan, Dailam, Tabaristan, Abaskun, Arran and Shirvan, before returning to the Volga Delta, where the Khazar ruler was given his share of the loot.
Thereupon, however, the Khagan’s elite guard force of Muslim mercenaries, the Arsiya (see below, under ‘Armies of the Khaganate’), supposedly demanded revenge for their co-religionists slaughtered by the Rus raiders; it is likely that some Arsiya came from those regions which had been attacked. Being unable to hold back these enraged warriors, who formed a significant part of his army, the Khagan merely warned the Rus. The resulting battle lasted three days, after which some 5,000 Varangian Rus fled to their ships and sailed up the Volga. However, when they reached the territory of the Burtas and Volga Bulgars they were almost wiped out by local forces who were themselves subjects of the Khazar Khaganate.
However, al-Mas’udi’s account is inconsistent, and the chronicler probably exaggerates the ‘mutinous’ aspect of the Arsiya’s behaviour; it seems more likely that the attack on the Rus raiders was pre-planned after a decision by the Khagan himself. Elsewhere, Gumilev writes that ‘the campaigns of the Rus to Gilan and to Azerbaijan were accomplished thanks to the support of the Judeo-Khazar government, which supplied the fleet with pilots and suitable ships’. According to Gumilev, the Khazar ruler had actually sent the Rus fleet against the Dailamites, a warlike Shia Muslim people of the south Caspian mountains who were playing an increasingly disruptive role in the turbulent politics of that region. Gumilev suggests that this Rus campaign may have been intended by the Khagan to punish the Dailamites for blocking the lucrative trade route between Khazaria and the heartlands of the Caliphate. However, the Rus raiders also attacked neighbouring Azerbaijan and parts of Armenia with which the Khazars perhaps had amicable trade agreements, thus ruining the Khagan’s strategic plans. Perhaps the Rus incurred the wrath of the Khagan simply by ignoring his instructions as to who they were to attack, and who to leave alone.
Gumilev is wrong in his suggestion that the Sunni Muslim Abbasid Caliphate was an ally of the Khazars. Islam was still a threat to the Khaganate, which would not allow Muslim scholars to carry Islam to the Volga Bulgars whose territory lay north of Khazaria. So why might the Khagan have decided to destroy the Rus army? Perhaps he thought that war was inevitable, and so decided to strike first, while also gaining some short-term benefit from portraying Khazaria as a defender of Muslims.
Only in the last years of the Khagan Aaron II’s reign did the Khazars’ mixture of cunning diplomacy and military force fail them. In 939 (see above, under ‘Campaigns also involving the Rus, AD 939–965’) the Rus saw an opportunity to avenge the disaster of 913–914 and, in alliance with the Byzantines, a Rus army struck at Khazaria just as a new ruler had either come to power or was about to do so◦– Joseph, the last effective Khagan.
Later, during the 950s, Joseph’s wide-ranging efforts to find allies would result in a correspondence between himself and Hasdai ibn Shaprut (Shafrut), a Jewish senior official in the government of the Umayyad caliph of the western Islamic state of al-Andalus (Islamic Spain and Portugal). This remarkable man, born in Jaen in southern Spain, was a physician, diplomat, and patron of science who wrote in Latin as well as Hebrew and Arabic. Though not a government minister, Hasdai negotiated alliances with sometimes distant powers on behalf of the Caliph of Andalusia, as well as being responsible for the collection of customs dues in Cordoba’s port. In 949 Hasdai had sent an embassy to the Byzantine capital, Constantinople, where it may have contacted Khazar officials or merchants. One way or another, a correspondence developed between Hasdai and Khagan Joseph, part of which survives embedded in other rare medieval Hebrew documents. In one of these Hasdai noted that Joseph was waging a ‘persistent war’ against the Rus, barring them from reaching Derbent overland or by sea. If the Rus had reached this point, Hasdai maintained, then they could have threatened the great Islamic city of Baghdad itself.
In practice, Khazar suzerainty over the Rus may have ended by 944, when the Rus agreed a new treaty with the Byzantine Empire. Just over 20 years later Svyatoslav I Igorevich, the ruler of Kievan Rus, launched a decisive campaign against Khazaria which destroyed the Khaganate. This time the Rus acted in concert with Ghuzz Turks, and possibly again with Byzantines. As a result, Tamatarkha (Tmutarakan) at the entrance to the Sea of Azov, as well as the major Khazar fortress of Sarkel, became part of Kievan Rus. Shortly afterwards Khazar lands along the lower Volga passed under the rule of Khwarazm, and were steadily Islamized. Around 985, Vladimir I of Kiev launched another sudden campaign against what was left of Khazaria, forcing the survivors to pay tribute. The Khazar Khaganate was finally dead.
The nomadic Pechenegs of the steppes had posed yet another threat to the Khazar Khaganate. Byzantine chroniclers maintain that there was almost constant hostility between the Khazars and these fellow Turks. (The Muslim chronicler al-Mas’udi states that Khazars and Pechenegs usually lived in peace, but since he wrote that the Pechenegs lived to the west of the Khazars he was probably confusing them with the Magyar Hungarians.)
Towards the close of the 9th century a local Khazar leader tried to block the Pechenegs’ migration, and formed an alliance with the Ghuzz Turks who lived south of the Ural Mountains. This resulted in a joint Khazar-Ghuzz army defeating the Pechenegs in 889, and forcing most of them to flee westward to the Black Sea steppes. In their place the Ghuzz took over the southern steppes of the Khazar realm, seemingly invited there by the Khazars.
As the Pechenegs moved westward they clashed with the Magyars who were, in turn, obliged to leave ‘Levedia’ (probably on the Don River) and migrate to Etelköz (Atelkuz), a territory between the Dneiper river and the Carpathian mountains. The Pechenegs also allied with the Balkan (as distinct from Volga) Bulgarian Tsar Simeon, who invaded Atelkuz in 895, slaughtering any Magyars he could find.
Thus, by the mid-10th century, the western steppes were occupied by nomadic Pechenegs who were nominally subject to the Khazar Khaganate. In reality, however, this Pecheneg migration had not only disrupted northern Khazaria, but also several Greek-speaking coastal settlements on the northern Black Sea (including the city of Phanagoria on the Taman pensinsula), several of which were abandoned. Furthermore, Pechenegs reportedly destroyed Bulgarian-Khazar settlements on the Crimean steppe. Ultimately the Pechenegs were among the main beneficiaries of the final collapse of the Khazar Khaganate, with domination of the steppes west of the River Volga passing to them after the 960s.