The Universal Ruler

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In 1200, the Mongols were a collection of disconnected nomadic tribes, constantly at war and surviving on the harsh steppes by foraging and herding. Within six years they would be united under one man, revolutionised into a fighting force that would make vassals of their formidable neighbours by 1227 and go on to conquer the largest contiguous land empire in human history. That man, who bore the title of ‘Universal Ruler’ (Genghis or Chinggis Khan), was one of the greatest military commanders and most bloodthirsty conquerors of all time.

Early Life

‘Genghis Khan’ was born Temüjin sometime around 1162 to the second wife of the Borjigin chieftain Yesügei. Mongol legends say that the infant came out of the womb clutching a blood clot in his right hand – an auspicious sign he would be a great warrior. This expectation was reinforced by his noble lineage: he was related to Khabul Khan, the first head of the Khamag Mongol confederation.

Yet the young Temüjin hardly seemed fit for his grand destiny: a quiet and timid boy, he was often picked on by his two older half-brothers and received little attention from his father. Despite his familial status, Temüjin had a harsh childhood, wracked by poverty and perilous danger.

This hardship began at age nine when his father Yesügei was poisoned by a group of Tatar warriors. With his father now dead, Temüjin was forced to return from the Khongirad tribe, where he was living with his betrothed, a young girl named Börte, to his own Borjigin clan.

Upon his return, Temüjin made a bid for his father’s old position as chieftain, but because of his age and the vulnerable circumstance of his family (now consisting only of two widows and six other children), he was spurned by the tribe and thrown out of it with the rest of his kin. No doubt this betrayal had a profound effect on the young Temüjin.

The family was left to fend for themselves on the Mongolian grassland – even their animals had been stolen by the cold-hearted tribesmen. Living in the desolate Khentii Mountains, the family survived on wild fruits and small game captured by the young boys, who adapted to living off the land.

Around the same time, he befriended a boy a few years older than himself from the Jadaran tribe, named Jamukha. He would eventually become Khan (ruler or chieftain) of his tribe, and the two soon became inseparable, three times swearing an oath to be each other’s anda (blood brother). In a tragic twist, they would ultimately become the bitterest of enemies.

Uniting the Mongols

Aged around sixteen, Temüjin returned to the family of Börte and finally married the woman to whom he was engaged. As a gift that would customarily be for his father, Temüjin was given a fine coat of black sable. Ingeniously, he used it to win support and protection; he offered the coat to Toghrul, the Khan of the Keraite tribe, as if to recognise him as his symbolic father, pledging himself as an ally (or vassal). Toghrul accepted the gift and thus gave Temüjin’s family his clan’s protection.

In 1184, a rival tribe raided his camp with 300 cavalrymen, kidnapping Börte. Consequently, Temüjin sought the help of his new patron and, with an army of 40,000, easily routed the Merkits, and Börte was rescued. This offensive showed Temüjin’s military leadership, and he soon amassed a large following.

Shortly afterwards, Temüjin and Jamukha performed the anda ceremony for the third time. As a result of his connections to other powerful Khans, Temüjin’s status continued to grow in his own tribe, the Borjigin, and indeed among all Mongols. His aspirations to unite the Mongolian tribes now seemed far more realistic.

However, as Temüjin and Jamukha grew in status, a rift opened. Jamukha was conservative, supporting the Mongolian aristocracy in the belief that elite positions should only be awarded to those of noble birth; Temüjin was more radical, supporting a meritocracy. As a result, the former mainly gained followers of elite families while the latter attracted a broader range of generally lower-class followers.

This culminated in a demand by Jamukha that they should divide up their camps, making derogatory remarks about Temüjin’s inferior bloodline. Temüjin and his followers left that night. Thus began the feud that would divide Mongolia.

Following Temüjin’s election as Khan of the Mongols by a kurultai (Mongol assembly) in 1186, Jamukha led an attack against the new Khan with a force of 30,000. Temüjin was decisively defeated in the Battle of Dalan Balzhut, with his followers scattered and many captured.

Much of the next ten years is lost to the historical records, but it was through this time that Temüjin rebuilt his strength. By 1197, he was notable enough that the Jurchen Jin, the powerful dynasty of northern China, sought him and Toghrul to attack the Tatars on their behalf, and powerful enough to win a resounding victory. It was from this restored position of strength that Temüjin continued in his efforts to unite the Mongols.

Much of this unification had to completed by conquest. His handling of defeated tribes was revolutionary, though brutal. Traditional Mongolian raids primarily involved individual horseback warriors looting the camps with little focus on capturing the tribesmen, thus leaving most of the tribe alive and eager for revenge. Temüjin ordered his soldiers to capture the clanspeople first, publicly executing the leaders and nobles while integrating the rest into his own clan.

Even looting was later revolutionised, instituting a system of collective looting and equal distribution. By promising to give a share of the spoils to the families of warriors killed in battle, he consolidated the support of his tribesmen and gained the absolute loyalty of his soldiers, while reducing their fear of death. Coupled with his unique style of meritocratically delegating authority, Temüjin gained many followers voluntarily too.

In 1201 Jamukha assembled his own kurultai of the leaders of the thirteen tribes still opposed to Temüjin. They elected him ‘Gur Khan’ (universal ruler), a title used by the previous Khan of the Qara Khitai – Toghrul’s uncle.

This move was an affront to both Temüjin and Toghrul, and so they raised an opposing coalition. They met in battle in the Ergune river valley. However, when a downpour signalled to Jamukha’s forces that the spirits were on Temüjin’s side, many of his soldiers panicked and fled. The remaining demoralised troops were quickly defeated and Jamukha forced to flee.

Yet in the harsh Mongolian world of constant betrayal, even Toghrul turned on the rising Temüjin. Due to two perceived slights, Temüjin’s coalition declared war on Toghrul’s Keraites, who allied himself with Jamukha. Nevertheless, Temüjin was victorious, and afterwards the Keraite tribe would dissolve.

This victory was in no small part due to his innovative reorganisation of his forces. Soldiers were divided into units of 10 men, then 100 men, then 1000, then 10,000. This allowed Temüjin to more precisely deploy his army, whereas steppe warfare previously had been little more than loosely organised hordes.

He continued to steadily conquer the remaining tribes, each time executing the aristocrats and integrating the rest. His position became so dominant that Jamukha’s own men handed him over to Temüjin – despite their enmity, he was granted an honourable death.

In 1206, Temüjin had unified the major tribes of the Merkits, Naimans, Keraites, Tatars and Uyghurs. In a kurultai, he was declared by all the Mongol chiefs to be ‘Genghis Khan’, the Ruler of the Universe.

Genghis Khan’s Conquests

A map of Asia and its empires c.1200. Credit: Thomas Lessman.

The following year, Genghis Khan initiated a series of raids into the Tangut Empire to the south of Mongolia on the pretext that his rival Nilqa Senggum (Toghrul’s son) was a fugitive there.

The Mongol forces found the Western Xia Tanguts to be a drastically different military opponent, whose highly fortified stone-walled cities rendered the traditional attacks of Mongolian horseback archers largely ineffective, though the nomadic warriors found far more success in engaging with Tangut forces on open grassland.

However, the Tangut Empire was the weakest state in northern China, making it a relatively easy target for Genghis Khan’s new army. They had recently been destabilised by political upheaval, with a bloody coup in 1206, and failed to form an alliance with the Jurchen Jin to defend against the imminent attack from the north. The Tanguts were unprepared to face the Mongolian incursion.

The larger Mongol invasion came in 1209, after Genghis had secured the submission of the Western Uyghurs. In April, the Mongol forces crossed the Ordos Desert and attacked the city of Wulahai. After defeating an army of horseback spearmen and infantry led by Gao Lianghui, the Mongols took the city and marched south along the Yellow River to the capital, Zhongxing.

Along the way they were forced to besiege the Kiemen fortress, guarded by an army of 70,000 (with an additional 50,000 reinforcements), to cross through the Helan mountains. After a two-month siege, the Mongols used their signature tactic of feigning retreat to lure out the garrison and easily destroyed the Tangut force.

With the road to the capital now open, Genghis’s forces reached Zhongxing but were unable to take the well-fortified city defended by 150,000 soldiers – twice the size of the Mongol army present. Genghis had attempted a novel tactic by diverting the Yellow River to flood the city, but due to the Mongol inexperience with engineering, the river instead flooded through their own camp.

However, the siege, while lengthy and contrary to their usual tactics, proved effective. The stagnant water supplies spread disease inside the city, and Mongols had destroyed their crops. With no hope of a relief force from the Jurchen Jin, Emperor Li Anquan submitted to become a Mongol vassal state, paying a tribute of textiles, falcons and camels, and even giving his daughter Chaka’s hand in marriage.

The invasion of Western Xia was Genghis’s first major foreign victory. Furthermore, it provided vital experience to the Mongol forces, especially in siege warfare. Genghis also gained control of caravan routes along the Silk Road, adding a substantial revenue stream for the emerging empire.

Despite this success, the Jin, the Manchurian rulers of northern China, sent a delegation to Genghis Khan’s court demanding that he submit to them as a vassal state. The Jurchen Jin had encouraged infighting in the steppes and frequently sent punitive expeditions north to enslave and kill Mongol nomads; the insult of ordering tribute from Genghis Khan added to the Mongolian century-long hatred of the Jin. In response, a kurultai in 1211 ruled in favour of war. 

The Jin too were in a weakened state. They faced endemic issues, as the ruling Jurchen people were a minority to the dominant Han Chinese, and so were unpopular and constantly faced rebellion. Furthermore, the state’s economy and fighting force were crippled by a long war with the Song Dynasty in the south of China and depleted further by widespread corruption, and there were ongoing famines caused by the Yellow River flooding, destroying prime farmland.

Genghis Khan’s forces were systematic in their approach to taking Jin cities, using their experience from Western Xia. They cleared out surrounding villages first, taking the male peasants to be used as conscripts or proverbial cannon fodder. Meanwhile, the influx of refugees into the cities caused panic, chaos and food shortages due to the sudden population increase.

When the Mongol army besieged Zhongdu, the Jin capital, in 1214, the pressure was so great that General Hushahu murdered the Jurchen emperor Yongji, enthroned Yongji’s young nephew and declared himself regent. Shortly after, the Jin government agreed to become a vassal to the Mongols, paying a vast tribute and presenting the Jurchen princess to Genghis as a consort.

Genghis Khan’s final major conquest was undertaken in 1219 against the Khwarezmian Empire in Central Asia, present-day Afghanistan and Iran. Following the unforgivable transgression of Shah Muhammad II executing Mongol diplomats sent to establish peaceful trade, a Mongol army of 100,000 invaded.

Genghis Khan divided his army into three, the first part of which crossed the Tien Shan mountains south of where the Khwarezmians were expecting the invasion and ravaged the Ferghana Valley. This unexpected manoeuvre, thought of by some as the Central Asian equivalent of Hannibal’s crossing of the Alps, caused panic in the Shah’s ranks.

Concurrently, the second Mongol army breached the Dzungarian Gate (a mountain pass) and besieged Otrar. However, this city, unlike the rest, did not surrender, fighting for five months until a traitor opened the gates to the Mongols. Even then, the remainder of the garrison held out for another month in the inner citadel before it was finally captured. They had delayed the Mongols and dealt them severe casualties, but it was ultimately futile. Tragically, Otrar became the first of many cities to have its entire population slain or enslaved before being razed by the Mongols. The captured governor Inalchuq was even said to have had molten silver poured into his eyes and ears.

While Shah Muhammah was preparing a strong defensive line along the Syr river, expecting the Mongol force at Otrar to march on the capital Samarkand, Genghis Khan’s third army, which he led personally, traversed the Kyzylkum Desert (considered impossible) to the north and fell suddenly upon Bukhara. The poorly defended city was taken quickly. As with Otrar, it was razed to the ground and its citizens slaughtered en masse.

Following their various successes, the Khan’s forces converged on the capital, Samarkand, in March 1220, using novel siege tactics and weaponry designed by captured Chinese engineers to breach the walls. On the third day, the 40,000 strong Khwarezmian garrison fell for the typical Mongolian feigned retreat and led a counter-attack, predictably resulting in a massacre. Therefore, despite the Shah’s unsuccessful attempts to relieve the city, the siege was short, with a surrender on the fifth day. Its 100,000 inhabitants were then slaughtered. In the next few years, the remaining Khwarezmian cities would nearly all be razed similarly.

Genghis Khan subsequently led another invasion into Western Xia following their earlier refusal to partake in the war against the Khwarezmian Empire. But before he could complete his second conquest of the Tangut state, the Khan mysteriously fell ill and died suddenly in August 1227. As per instructions issued years prior, he was buried in an unmarked grave in Mongolia, likely at his birthplace near the Onon River.

His son Ögedei succeeded him, and his Mongol Empire would reach its zenith under his grandson Kublai Khan, though it would fracture shortly after Kublai’s death.

The Mongols were inhumane in their slaughter of tens of millions of people in their conquests. This ruthlessness promoted by Genghis Khan was crucial to Mongol success and so is inextricable from it.

While it is ultimately an afterthought, it is still worth considering the Mongol Empire beyond only its conquest and slaughter. Early on in the empire, Genghis established freedom of religion, abolished the kidnapping of women, adopted a central writing system and a law code, the Yassa. Perhaps of greatest significance was the increase in trade over the Silk Road network between East and West caused by the empire linking the two, where before antagonistic religious empires had prevented free passage – a legacy that lasted hundreds of years after Genghis’s death.

Genghis Khan was a man who contained multitudes. He was of noble birth but endured significant hardship in his early life, which informed his belief in meritocracy and that birth ultimately should not matter. He instituted many tolerant reforms and yet was brutal and unforgiving to his enemies.

However, he had one characteristic that was unmitigated: he was a military genius, and perhaps the greatest conqueror the world has ever known.

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