The conquest of the Khwarezmian Empire, also known as the Khwarezm-Shah dynasty or the Khwarezmian Shahdom, was the most extensive and the most destructive of the campaigns of Genghis Khan. The campaign of 1219-1221 was triggered by the treacherous execution of two of Genghis Khan’s envoys by the Khwarezmian Shah Muhammad II, and it resulted in the destruction of one of the most powerful states in the medieval world. The campaign is also famous for the sack of several of the most important cities of the Islamic East, including Bukhara, Samarkand, Merv, Urgench, Balkh, and Herat, and it was a major turning point in the history of the Islamic world.
The Khwarezmian Empire was, at the time of the Mongol invasion, one of the most powerful states in the world. The empire had been founded in the late eleventh century by the Khwarezm-Shah dynasty, a Turkish slave dynasty that had risen to power in the service of the Seljuk Empire. The empire had been greatly expanded in the late twelfth and early thirteenth centuries by the Khwarezm-Shahs Ala al-Din Tekish and his son Muhammad II, and at its height the empire stretched from the Indus to the Tigris and from the Syr Darya to the Persian Gulf.
The Causes of the War
The causes of the war between the Mongols and the Khwarezmian Empire are complex, but the immediate cause was the execution of two of Genghis Khan’s envoys. In 1218, Genghis Khan sent a small group of envoys and merchants to the Khwarezmian court to negotiate a trade agreement. The envoys were received at the border city of Otrar by the local governor, who, on suspicion of spying, executed the envoys and confiscated the goods. The governor, a man named Inalchuq, was acting on his own authority, but the Khwarezmian Shah Muhammad II refused to punish him, and Genghis Khan was given no satisfaction.
Genghis Khan responded by sending a second group of envoys, this time led by two of his most trusted officials, to demand the surrender of the governor. The Shah, who is reported to have been advised against the move by some of his counselors, executed one of the envoys and sent the other back with his beard shaved — a deliberate insult, by the customs of the steppe. The insult was a fatal mistake. Genghis Khan, who had long been planning a campaign against the Khwarezmian Empire, used the insult as a pretext to launch a major invasion.
The Mongol Invasion
The Mongol invasion of the Khwarezmian Empire began in 1219, with a force of perhaps 100,000 to 150,000 men, organized into several columns under the command of Genghis Khan, his sons Jochi, Chagatai, and Tolui, and his most trusted general, Subutai. The Mongol force crossed the Syr Darya and laid siege to the city of Otrar, where the offending governor was based. The siege lasted for several months, but the city eventually fell and the governor was executed in a particularly gruesome manner — molten silver was poured into his eyes and ears, in keeping with the Mongol custom of punishing the guilty in kind.
After the fall of Otrar, the Mongol columns fanned out across the Khwarezmian Empire. The main body, under Genghis Khan, marched on the city of Bukhara, which fell in February 1220. The city of Samarkand fell in March 1220, after a long siege. The city of Urgench, the capital of the empire, fell in April 1221, after a long and difficult siege. The cities of Merv, Balkh, and Herat fell in turn, each after a siege that was more or less destructive depending on the resistance that the city put up.
The conquest was marked by extraordinary violence. The Mongols had a reputation for treating cities that resisted harshly, and the cities of the Khwarezmian Empire that resisted were treated with particular brutality. The city of Merv, which was one of the largest and most populous cities in the world at the time, was destroyed so completely that it never recovered; estimates of the death toll range from hundreds of thousands to over a million. The city of Urgench was depopulated, and the few survivors were deported to Mongolia. The city of Herat was depopulated, and the surviving population was deported to other parts of the empire.
The Battle of the Indus
The only major military reverse that the Mongols suffered during the campaign was at the Battle of the Indus in 1221. The Khwarezmian prince Jalal al-Din, the son of the Shah, had rallied the remnants of the Khwarezmian army in Afghanistan and was leading a campaign of resistance against the Mongols. The two armies met on the banks of the Indus, and the Mongols suffered a significant defeat. Genghis Khan, who was present at the battle, is reported to have been impressed by the courage of Jalal al-Din, and he watched the battle from a nearby hill.
Genghis Khan chased Jalal al-Din across the Indus, but the Khwarezmian prince escaped into India. The Mongols, who were not equipped for the climate of the Indian subcontinent, did not pursue the chase, and Jalal al-Din eventually made his way to Delhi, where he entered the service of the Sultan Iltutmish. Jalal al-Din continued to resist the Mongols for several more years, and he was eventually killed in 1231 while on campaign in Kurdistan. The Battle of the Indus was the only major military reverse that Genghis Khan suffered in his career, and it was a reminder that even the most successful military commander can be defeated.
The Consequences of the Conquest
The conquest of the Khwarezmian Empire was a major turning point in the history of Eurasia. The Khwarezmian Empire, which had been one of the most powerful states in the Islamic world, was destroyed, and the destruction opened up Central Asia to Mongol rule. The campaign also had a profound effect on the populations of the conquered territories, with millions of people killed, deported, or displaced. The destruction was so thorough that the modern world has only the dimmest recollection of the cultural richness of pre-Mongol Central Asia.
The conquest also had important consequences for the Mongol Empire itself. The campaign introduced the Mongols to the riches of the Islamic world, and it gave them a taste for the luxury goods of the Islamic East. The campaign also introduced the Mongols to the administrative traditions of the Islamic world, and the Mongols began to use Persian and Turkic administrators in the administration of their empire.
The conquest of the Khwarezmian Empire was, in this sense, a major step in the transformation of the Mongols from a steppe people to a Eurasian imperial dynasty. The Mongols were no longer just a steppe army; they were now a Eurasian power, with a sophisticated administration, a wide network of trade routes, and a deep interest in the cultures of their subject populations.
Sources
- John Andrew Boyle, trans., The History of the World Conqueror by Juvaini (2 vols., Manchester: Manchester University Press, 1958) — the principal Persian account of the campaign, by a Persian historian who was himself in the Mongol service.
- W. M. Thackston, trans., A Critical Edition of the Compendium of Chronicles by Rashid al-Din (Cambridge, MA: Harvard, 1998–1999) — the second principal Persian account, written c. 1300.
- John Man, Genghis Khan: Life, Death and Legacy (London: HarperCollins, 2004), ch. 10–12.
- David Morgan, The Mongols (2nd ed., Oxford: Blackwell, 2007), ch. 3.
- Timothy May, The Mongol Conquests in World History (London: Reaktion, 2012), ch. 4.
- Peter Jackson, The Mongols and the West, 1221–1410 (London: Pearson, 2005), ch. 1.
- W. Barthold, Turkestan Down to the Mongol Invasion (London: Luzac, 1928; 4th ed. 1977) — the classic treatment of pre-Mongol Central Asia.