Within a single human lifetime — about fifty years — a small tribe of nomads from the steppe between Lake Baikal and the Gobi desert built the largest contiguous land empire in human history. At its peak in 1260 it stretched from the Korean peninsula to the Carpathians, from the Siberian taiga to the Persian Gulf — about 24 million square kilometres and a quarter of the planet's population. It all began in 1206, when a kurultai by the river Onon proclaimed a 44-year-old chief named Temüjin as Genghis Khan — "universal ruler." Over the next 21 years he personally conquered the Jin in northern China, the Tangut state of Western Xia, and the Khwarazmian Sultanate from the Aral Sea to the Indus — and died on campaign in 1227. His sons and grandsons over the following 30 years took Kyiv, Baghdad and Damascus, reached the Adriatic and Hungary, and were stopped only in 1260, in Palestine, where the Mamluks of Sultan Qutuz broke the Mongol vanguard at Ain Jalut. It is a short, terrifying and astonishingly efficient story — and it changed both Europe and Asia for ever.
Who was fighting whom
On one side — the Mongols: the Borjigin clan and the steppe peoples united by Genghis Khan into a single state-army. At the start of the 13th century there were no more than a million of them, of whom about 100,000—200,000 were fighting men. Their chief weapon was not numbers but discipline, mobility and the composite bow: a Mongol horseman could cover 100 kilometres a day without difficulty, kept three to five spare horses with him and could shoot at full gallop in any direction. The army was organised in tens, hundreds and tumens of 10,000; if one man fled, his entire ten was punished. Genghis Khan built a meritocracy — commanders were chosen for ability, not birth — and laid down the Great Yasa: a written code that subjected everyone to the same rules.
On the other side — practically every great civilisation in Eurasia. Steppe rivals: Tatars, Keraites, Naimans, Merkits — tribes who had fought the Mongols for centuries and whom Temüjin had broken by 1206. The Jin empire in northern China (the Jurchen dynasty, capital Zhongdu — modern Beijing) — a populous state with million-strong armies and gunpowder weapons. The Tangut Western Xia in northern China — a Buddhist state that controlled the Silk Road. The Khwarazmian Sultanate of Muhammad II (1200—1220) — the largest Muslim state of Central Asia, with Samarkand, Bukhara and Urgench. Rus, split into principalities; Hungary and Poland; the Abbasid Caliphate at Baghdad under Caliph al-Musta'sim; the Ayyubids of Syria and the Mamluks of Egypt — the last people who managed to stop the Mongol machine.
Phases of the Mongol conquests
The story of the Mongol conquests breaks naturally into five phases. The birth of Genghis Khan (1162—1206): the childhood of Temüjin, the murder of his father, survival on the steppe, alliances with Toghrul and Jamukha, the slow unification of the tribes and the Kurultai of 1206. The conquest of China (1207—1218): the subjugation of Western Xia, the war with the Jin, the fall of Zhongdu (Beijing) in 1215 and the arrival of the adviser Yelü Chucai. The Khwarazm campaign and the death of Genghis Khan (1219—1227): the Otrar massacre as pretext, Bukhara, Samarkand, Urgench; Subutai's raid through the Caucasus and the battle of the Kalka in 1223; death during a second campaign against the Tanguts. Batu's western campaign (1229—1241): Great Khan Ögedei, the finishing of the Jin, Vladimir and Kyiv, Legnica and Mohi — and a sudden return because of Ögedei's death at Karakorum. The breakup of unity (1242—1260): Great Khan Möngke, Hülegü's campaign and the taking of Baghdad in 1258, defeat at Ain Jalut and the division of the empire into four khanates. The page ends with sections on the legacy and an epilogue.
Phase 1. The birth of Genghis Khan (1162—1206)
Temüjin was born on the steppe by the river Onon around 1162 — by legend with a clot of blood in his fist, which the shamans took as the sign of a future leader. The first 25 years of his life are a story of survival: the murder of his father, the family's expulsion from the tribe, hunger, slavery, a return from nothing. Only a man who had known what it was to freeze in a tattered felt tent could build a military machine so ruthless and so precise.
The father's death and survival on the steppe
Temüjin's father — Yesügei Baghatur, chief of a small Mongol clan, the Borjigin — was poisoned by Tatars at a feast when Temüjin was about nine years old. By steppe custom a widow with small children had no right to stay in the tribe — and the clan at once abandoned Yesügei's family in mid-winter. Temüjin's mother Hoelun, with six children, survived on her own, living on roots, wild berries and small animals. These were the years that made Temüjin what he became: a hungry adolescent who learned to trust no one not bound to him by blood or by oath.
At twelve Temüjin killed his half-brother Bekter over a dispute about hunting prey — the first show of the cruelty that would later define his rule. Soon afterwards he was captured by a hostile clan, the Tayichi'ud, and held in a wooden pillory — the cangue. He escaped one night, taking advantage of a feast among his captors, and made his way back to his family. At sixteen he married Börte — the bride his father had chosen for him. The young bride was soon kidnapped by Merkits; Temüjin could only recover her with the help of his father's old friend Toghrul, khan of the Keraites, and his own anda (sworn brother) Jamukha. Börte's first son, Jochi, was born shortly after her rescue — and Temüjin loved him as a son all his life, though every camp whispered that Jochi's father was a Merkit.
Alliance with Toghrul, the break with Jamukha
Over the next two decades — roughly from 1185 to 1205 — Temüjin slowly, alliance by alliance, knitted the Mongol tribes together. The key was his friendship with Toghrul, khan of the Keraites — a strong Nestorian-Christian state south of the Mongol pastures. Together they broke the Tatars (1196), for which Toghrul received from the Jin emperor the title of "Wang Khan" (king). Temüjin methodically destroyed every hostile clan that had killed his father or persecuted his family: of the Tatars who had poisoned Yesügei, every man taller than a wagon wheel was put to the sword. This was not random cruelty — it was the deliberate liquidation of a blood-debt.
With Jamukha — the childhood sworn brother with whom Temüjin had three times exchanged the oath of anda — relations soured once it became clear that both men wanted the same thing: to be the sole lord of the steppe. Around 1187 they separated. In 1201 a coalition of tribes led by Jamukha proclaimed him Gür Khan — "universal ruler" — and marched against Temüjin. Temüjin defeated them, but Jamukha escaped. In 1203 Temüjin defeated Toghrul himself — who under his son Senggum's influence had turned against his protégé — and put the Keraites to the sword; the whole elite of their state was destroyed or absorbed. The last great rivals were the Naimans in the west; Temüjin broke them in 1204 at the battle of Mount Nakhu. Jamukha, who had fled from his former sworn brother to the bitter end, was handed over to Temüjin by his own men — and Temüjin, true to the customs of the steppe, ordered him a "noble death": without spilling blood, that is, by breaking his back.
The Kurultai of 1206
In the spring of 1206, on the banks of the river Onon — where the boy Temüjin had been born — a great kurultai assembled: all the chiefs of what was now a unified Mongolia gathered to acknowledge a single authority. The shaman Kokochu (also known as Teb-Tengri) proclaimed in the name of the Eternal Blue Sky that Temüjin was henceforth Genghis Khan, "universal ruler" (the exact etymology is still debated — perhaps from Turkic tengiz, ocean; that is, "oceanic khan," khan without limits). He was about 44 years old.
Genghis Khan at once rebuilt his new state-army. He divided the entire Mongol male population into tens, hundreds, thousands and tumens of 10,000 — across the old tribal lines. Now a Keraite, a Naiman and a Tatar might serve in the same ten, with a commander chosen for ability, not for birth. If one man deserted, his entire ten paid the price. Command of tumens — the highest military rank — was given to about twenty of his most trusted men; among them the four "dogs of war": Jebe, Subutai, Khubilai (not to be confused with his grandson Kublai Khan) and Jelme. He created the khan's personal guard, the kheshig, 10,000 elite soldiers. He codified the Great Yasa: a written body of law that, among other things, forbade theft of livestock, required religious tolerance for all faiths, regulated hunting, and prescribed the death penalty for desertion, treason and cheating a merchant. All this Genghis Khan did in a year or two — and in 1207 he was ready for his first campaign abroad.
Phase 2. The conquest of China (1207—1218)
Having united the steppe, Genghis Khan turned south — to lands where for centuries the Mongols had been tributaries and sometimes slaves of the rich Chinese states. The first target was Western Xia — a Tangut kingdom lying between the Mongol pastures and the Silk Road. The second was the mighty Jin empire, which ruled northern China. For the first time a steppe people stormed real Chinese walls — and the technique was learned from captive engineers.
Western Xia, 1209
Tangut Western Xia (Xi Xia in Chinese) was a Buddhist state with its own complex syllabic script, a capital at Zhongxing (modern Yinchuan) and a population of about three million. It controlled a key stretch of the Silk Road — so its merchants saw the nomads as dangerous but necessary partners. In 1207—1209 Genghis Khan launched three campaigns against Western Xia; the third was the hardest. The Tanguts shut themselves up in their capital and trusted that the Mongols, without siege engines, would never breach the walls. Genghis Khan, who had not yet learned to take cities, tried a clever solution: he diverted the waters of the Yellow River onto the city. But the dam broke, and the water flooded the Mongol camp itself — the Tanguts only laughed from the walls.
The Tanguts surrendered all the same. The siege had lasted about six months; by the winter of 1209, hunger and disease had set in at Zhongxing. Emperor Xiangzong acknowledged himself the vassal of Genghis Khan, gave a daughter in marriage and promised military aid in future campaigns. This was Genghis Khan's first conquest beyond the steppe — and the first great lesson: a mobile nomad army that cannot take cities cannot hold a civilisation it has conquered. Genghis Khan at once began enlisting engineers — Chinese, Tangut, later Persian. By the end of the 1210s the Mongol siege corps could do it all: undermining, rams, throwing engines, Greek fire, and even early gunpowder artillery borrowed from the Jurchens.
The Jin and the fall of Zhongdu, 1211—1215
In 1211 Genghis Khan crossed the Great Wall of China — or rather its 13th-century predecessors, which did not yet form a single line — with an army of about 100,000. Before him lay the Jin empire — the Jurchen dynasty that ruled northern China from the Yellow Sea to the desert and could put half a million men in the field. At first the Mongols could hardly take any city; the first four years were a series of raids — the steppe men came out of the forests and the grasslands, burnt the fields, drove off the livestock, and went home again. The Jin emperor Wudabu thought he would outwait the Mongols as he had outwaited the Huns and Khitans before them. He was wrong.
By 1213 the Mongols had their own siege engines, their Chinese engineers and three years' experience of war. Genghis Khan's army came through the Juyong Pass and onto the plain before Zhongdu — modern Beijing — the greatest city of the Jin, with a population of about a million. The city's walls were 12 metres high and more than 22 kilometres in circumference. Genghis Khan locked it in a blockade, and in May 1215, after several months of starvation (some chronicles claim the inhabitants ate their own children), Zhongdu fell. The city burned for almost a month; according to certain Arab accounts, an envoy of the shah of Khwarazm a year later still saw heaps of charred bones on the outskirts. Among the prisoners Genghis Khan took with him was a young Khitan official in Chinese service named Yelü Chucai. He would become one of the most important Mongol administrators and the man who would persuade Genghis Khan and Ögedei that it was more profitable to take taxes from subjects than to kill them: "the empire was won on horseback, but it cannot be ruled from a saddle."
Phase 3. The Khwarazm campaign and the death of Genghis Khan (1219—1227)
The best documented of all Genghis Khan's campaigns — and the bloodiest. The pretext turned out to be commercial: the murder of Mongol merchants in the border town of Otrar. The campaign itself lasted less than three years, but it wiped one of the richest Muslim states of its day from the map. In the same years Subutai and Jebe carried out the legendary reconnaissance raid around the Caspian, brought the Mongols into contact with Rus and returned home having ridden round half of Eurasia. Genghis Khan himself died on campaign in 1227, before he ever saw the Western lands he had already conquered.
Otrar and the revenge, 1218—1219
In 1218 Genghis Khan, then still busy with the Jin and the freshly conquered Naimans in the west, sent to the Khwarazmshah Muhammad II a great trade caravan — about 500 camels, 100 merchants, mostly Muslims and Central Asians in Mongol service. Caravans of this size were a diplomatic message: "let us trade, not fight." The Khwarazmian Sultanate was then at the height of its power — Sultan Muhammad II ruled all of Central Asia from Iraq to the Aral Sea, with the splendid cities of Bukhara, Samarkand, Urgench, Balkh, Herat and Ghazni.
The caravan arrived at the border town of Otrar on the Syr Darya. Otrar's governor, Inalchuq, a kinsman of Sultan Muhammad, declared the merchants spies and ordered all of them executed, seizing their goods. When Genghis Khan heard, he sent three envoys to the sultan demanding the guilty man be handed over. Muhammad answered with contempt: he had the chief envoy executed and the beards of the other two singed off — the gravest of insults to a Muslim — and sent them back. It was the final affront, which Genghis Khan, as he told a chronicler himself, "could not wipe away with any sword I have." In the summer of 1219 a Mongol army of about 150,000—200,000 — larger than any before — set out west. The Khwarazmshah, with nearly half a million men of his own, made a catastrophic mistake: he dispersed his troops among the cities of Transoxiana instead of fighting a pitched battle. It meant that Genghis Khan could deal with them one at a time.
Bukhara and Samarkand, 1220
At the start of 1220 Genghis Khan did what everyone had thought impossible. Instead of taking the direct road through Otrar (which he left to his sons Jochi and Chaghatai — and which they took in five months; governor Inalchuq ended his life with molten silver poured into his ears), he himself with the elite of his army crossed the Kyzylkum desert — 500 kilometres of waterless sand — and appeared suddenly out of the north under the walls of Bukhara. The city surrendered almost without a fight, the garrison attempted a sortie and was cut down in the open. Genghis Khan rode into Bukhara, watered his horses in the river and climbed the minaret of the main mosque — at first taking it for the sultan's palace. Told that it was the House of God, he came out and in the courtyard of the mosque told the people that they were "the punishment of God for their sins." The city was sacked and burned; the craftsmen were marched off to Mongolia, the other inhabitants — up to 30,000 — used as living shields in the next assaults.
Three weeks later Samarkand fell — the richest city in Central Asia, with a population of about 500,000. The garrison was Turkic, and Genghis Khan tricked it into leaving the city, where it was destroyed. The craftsmen — about 50,000 of them — were sent to Mongolia; the other inhabitants ransomed themselves with vast sums or were put to the sword. Khwarazmshah Muhammad, who had been in the city a week before the siege, fled west. Genghis Khan sent Jebe and Subutai after him with two tumens — and it was this detachment that became the legendary raid.
Urgench and the end of Khwarazm
The last great city of the sultanate was Urgench — capital of the Khwarazm province in the Amu Darya delta, with a population of about 1.2 million. The city was held by the most fanatical of the Turkic garrisons, and its capture became the hardest of the whole campaign: the siege lasted about seven months, from the spring to the autumn of 1221. The siege army was led at once by three of Genghis Khan's sons — Jochi, Chaghatai and Ögedei — and they could not agree on a command; Jochi wanted to take the city intact (since it was to be part of his appanage), Chaghatai insisted on total destruction. In the end Genghis Khan handed command to the third son, the youngest Ögedei. When Urgench finally fell, the Mongols methodically razed quarter after quarter — and at last broke the irrigation dam of the Amu Darya, drowning the ruins. The Persian chronicler Juvayni wrote that out of a million inhabitants no more than 10,000 craftsmen survived. Urgench never recovered its old greatness — the very course of the Amu Darya later shifted away.
Khwarazmshah Muhammad, hunted by Jebe and Subutai, died in December 1220 on a tiny island in the Caspian — of exhaustion and dysentery, without a coin and without a single companion. His son Jalal ad-Din — a gifted commander — tried to hold out in Afghanistan, beat the Mongols at the battle of Parvan in 1221, but was then crushed by Genghis Khan himself in the battle on the Indus. By legend, seeing his army destroyed, Jalal ad-Din in full armour rode his horse off a cliff into the Indus and swam to the other bank. Genghis Khan, watching from the opposite shore, is said to have told his sons: "this is the kind of son a real father begets." Jalal ad-Din fled to Delhi, returned, and fought the Mongols for another ten years, but it could no longer save anything. By 1222 the Khwarazmian Sultanate was off the map.
Subutai and Jebe's raid, the Kalka 1223
While Genghis Khan was finishing off Khwarazm, his two best generals carried out the most fantastic raid in pre-modern military history. Jebe and Subutai with two tumens (about 20,000 horsemen) pursued Sultan Muhammad as far as the Caspian, and then, with Genghis Khan's leave to "scout," went round the sea from the south — through Iran and the Caucasus. They defeated the Georgian army of King George IV in 1221, then crossed the pass of Derbent into the Ossetian and Kipchak steppes. Here, in the northern foothills of the Caucasus, they met the Cumans (Kipchaks), whom no European chronicle had ever seen before — and beat them too.
The Cuman khan Kotyan fled to his son-in-law — the Kyivan prince Mstislav the Bold — and asked the Rus for help. The southern Rus princes — of Kyiv, Chernihiv, Halych — raised a great combined army (up to 80,000 by the chronicle) and marched east. On 31 May 1223, on the river Kalka (modern Kalmius in the Donetsk region), Subutai and Jebe used the classic Mongol tactic: a feigned retreat over several days, until the Rus forces had strung out their column, then a counter-attack from two sides. The Rus army was destroyed entirely: six princes were killed, among them Mstislav of Kyiv, whom the Mongols suffocated under planks on which they sat and feasted. It was the first meeting of Rus with the Mongols — and the first warning of what was coming. But Subutai and Jebe did not press further: they returned home through the Volga, having ridden around half of Eurasia in four years. Jebe died on the way of illness; Subutai brought his tumens to Genghis Khan in 1224.
The death of Genghis Khan, August 1227
Returning to Mongolia in 1225, Genghis Khan found that the Tanguts of Western Xia — his first conquered subjects, who were supposed to send troops to the Khwarazm campaign — had in fact sabotaged the promised aid. The Tangut emperor Xianzong had haughtily replied to his envoy: "if your khan has so little army that he needs mine, why does he call himself khan?" Genghis Khan, now 64, with a damaged back after a fall from his horse the previous year, set out on a last campaign — to destroy Western Xia. The campaign ran from 1226 into the summer of 1227. The Tangut cities fell one after another; the capital, Zhongxing, was under siege.
In August 1227, before Zhongxing's final surrender, Genghis Khan died in his camp at about 65 years of age. The exact cause is unknown: according to different sources, from the after-effects of the fall from his horse, from dysentery, from a poisoned arrow, from a wound inflicted by a captured Tangut princess. Before he died, he gave two orders. First: keep his death secret until the end of the Tangut campaign — so that the empire should see no weakness. Second: when Zhongxing surrendered, kill the entire Tangut elite down to the last man. Both orders were carried out. Genghis Khan himself was buried in secret — by legend in the mountains of Burkhan Khaldun (today in north-eastern Mongolia); the funeral procession killed everyone it met on the road, so that no one should know the place. Thousands of horses were driven over the grave to trample out any trace. Genghis Khan's tomb has never been found, despite centuries of searching and modern archaeological expeditions.
Phase 4. Batu's western campaign (1229—1241)
Before he died, Genghis Khan divided the empire among his four sons as appanages; over them all, however, the authority of the Great Khan at Karakorum was preserved. The first Great Khan was the third son, Ögedei (1229—1241) — a good-natured drunkard but a capable organiser, who finished what his father had begun. Under him began the great western campaign — the farthest and most terrible Mongol raid. It was led by Genghis's grandson Batu, Jochi's son, with the strategist Subutai at his side. He destroyed Rus, took Poland and Hungary, reached the Adriatic — and then, suddenly, in March 1242, turned his horses back. Europe was saved by Ögedei's death.
Ögedei and the end of the Jin, 1234
At the kurultai of 1229 Genghis Khan's third son Ögedei was proclaimed Great Khan, in accordance with his father's will. The eldest, Jochi, had died before his father (1227), some suspect by poison sent by Genghis Khan himself, since their relations had long been strained. The second, Chaghatai, was hot-tempered and stubborn and himself acknowledged Ögedei the better choice. The fourth, Tolui, received the "homeland" of Mongolia and was nominally regent between Genghis Khan's death and Ögedei's election. Ögedei built at Karakorum the first proper capital of the empire — a city of white palaces, mosques, churches and Buddhist shrines, for the khan invited foreign craftsmen from every corner of the world.
The first thing Ögedei finished was the destruction of the Jin. In 1230 he himself marched south, against the remnants of the Jurchen state that had withdrawn beyond the Yellow River to a new capital, Kaifeng. Ögedei's army and Tolui's, in alliance with the southern Chinese Song dynasty, besieged the last Jin emperor Aizong at Caizhou. In February 1234 the Jin ceased to exist; the emperor hanged himself, and his body was cut in half — one half taken to the Mongols, the other to the Song. Thus the Jurchen empire, which had dominated the Mongols for centuries, vanished. All of northern China was now Mongol — and the young adviser Yelü Chucai was already at work on a system of taxation that filled Ögedei's treasury with silver.
The conquest of Vladimir and Kyiv, 1237—1240
At the kurultai of 1235 Ögedei decided to send a great western army — about 130,000 horsemen under the command of Genghis's grandson Batu (Batu Khan) and the veteran Subutai. This was not an ordinary raid like that of 1223 — it was a campaign of permanent conquest. In the autumn of 1237 the Mongols crossed the Volga and fell on north-eastern Rus. Riazan fell first, in December 1237 — the city was utterly destroyed, the population butchered, Prince Yuri Ingvarevich killed. Next came Kolomna, Moscow (then a small fortress), and Vladimir.
In February 1238 the Principality of Vladimir fell — the most powerful state in north-eastern Rus. Grand Prince Yuri Vsevolodovich tried to raise an army on the river Sit, but was defeated and killed there on 4 March 1238. Batu pressed further north, but spring mud and impassable roads stopped him short of Novgorod — and this saved the Novgorod Republic from destruction. He then turned south, and in 1240 reached Kyiv. The mother of Rus cities was defended by the chiliarch Dmytro — sent by Prince Danylo of Halych, since Kyiv's own prince Mikhail had fled. On 6 December 1240 Kyiv fell. What happened next is hard to convey: by the chronicle, the Mongols destroyed almost the whole population; when six years later the papal envoy, the Franciscan Giovanni del Pian del Carpine, rode through, there remained in Kyiv, in his words, "not more than two hundred houses" of the ten thousand that had once stood. The Church of the Tithes collapsed — by legend — from the weight of people who had taken refuge on its roof and choir lofts.
Legnica and Mohi, April 1241
In the winter of 1240—1241 Batu split his army into three columns and pressed west. The southern column went through the Halych-Volyn principality (where Prince Danylo of Halych had to flee to Hungary), Sandomierz, Krakow. The central column went through Volodymyr-Volynskyi and southern Poland. The northern column went into Silesia. The Polish and German nobles gathered a combined army under the Silesian duke Henry II the Pious. On 9 April 1241, at Legnica (today Legnica in Poland), Mongol tactics did their work: feigned retreat, counter-attack, encirclement. The Polish-German army was annihilated, Henry was killed, his head fixed on a spear and paraded through the cities. The Bohemian king Wenceslas I, marching to help with an army a day's ride away, turned home.
Two days later, on 11 April 1241, the second Mongol army in Hungary broke the Hungarian army of King Béla IV at the battle of Mohi (more precisely, on the river Sajó). It was an even greater catastrophe — Hungary, with a population of 15 million, was the largest state in Central Europe; Béla IV fled to Croatia, then to an island in the Adriatic. The Mongols rode through Hungary in the summer of 1241 and the winter of 1242, slaughtering as they went, and by the spring of 1242 one tumen was already preparing a march on Vienna. Western Europe froze in horror — Pope Gregory IX, Emperor Frederick II, King Louis IX of France daily expected the Mongols to appear. The pope wrote to Béla IV that he was ready "to send the poor and the monks on Crusade against the Tatars." It looked as though nothing could save Europe — no army, no fortress.
The miracle: Ögedei's death and the turn-back, March 1242
On 11 December 1241, at Karakorum, Great Khan Ögedei died — by most accounts of his drinking (his elder brother Chaghatai had warned him against it all his life). He was 55. The news reached Batu near Vienna in March 1242 — and it was Europe's miracle. By Mongol custom all Chinggisid princes had to appear at a kurultai to elect a new Great Khan; Batu, who had his own claim to the throne, could not afford to leave his army in Europe. In March 1242 he ordered the horses turned. Forward tumens were already within 50 kilometres of Vienna; others stood by the Adriatic. They all turned back.
Europe did not at once understand what had happened. King Béla IV returned to a ruined Hungary, where he had to take a fresh census and rebuild the country from nothing; Rus lived under Mongol rule — Batu founded the Golden Horde with its capital at Sarai on the lower Volga — and paid tribute for 237 years, until the Battle of Kulikovo in 1380 and the final "Stand on the Ugra" in 1480. The kurultai of 1246 elected Ögedei's son Güyük Great Khan, but he ruled only two years and died in 1248. Only in 1251 did the throne pass to Möngke, son of Tolui — and it was almost a change of dynasty: from now on the senior branch of the Chinggisids was the Toluid, not the Ögedeid. Ögedei's heirs were systematically eliminated or exiled in the following years.
Phase 5. The breakup of unity (1242—1260)
On paper the empire still remained one, but in fact it held together only by the authority of a particular Great Khan. At first this was Möngke — an energetic, sober, serious ruler under whom the empire made two more great leaps: Hülegü took Baghdad, Kublai began the final conquest of southern Song. But Möngke's death in 1259 was the end of unified rule. The defeat at Ain Jalut in 1260 showed the limit of Mongol capacity — and from then on the four khanates began to live their own separate lives.
Möngke Khan and his reforms, 1251—1259
Möngke, son of Tolui and grandson of Genghis Khan, became Great Khan in 1251. He was, all contemporaries said, very like his grandfather: stern, hard-working, focused. He spoke five languages, loved mathematics and astronomy, kept Persian astronomers and Armenian monk-translators at his court. The first thing he did was to carry out a census of the whole empire: for taxation, for recruitment and for the issue of charters of rule. It was the first and only time that the entire Mongol territory from Korea to Hungary was subjected to a single administrative count.
Möngke sent his two younger brothers to lead the great campaigns of conquest. The younger Kublai (the future Kublai Khan, founder of the Yuan dynasty) — south, for the final conquest of southern Song. The other younger brother, Hülegü — west, to Iraq, Persia and Syria; his task was to destroy the sect of Assassins in northern Iran and to make the caliph of Baghdad acknowledge Mongol rule. Möngke himself in 1257 took the field against the Song in person — and there, in southern China, in mid-August 1259, he died. The exact cause is unknown: malaria, dysentery, drink, or perhaps a wound. He was 51. His death again raised the question of succession — but this time both younger brothers, Kublai and Ariq Böke, proclaimed themselves Great Khan and went to civil war with each other. The empire of Genghis Khan would never be put back together as one.
Hülegü and the fall of Baghdad, 1258
Möngke's younger brother Hülegü (1218—1265) carried out his western mission with brilliance and horror. First, in 1256, he destroyed the sect of the Assassins in northern Iran — storming the legendary fortress of Alamut, which had been thought impregnable for 170 years. Then he moved slowly west, to the heart of Islam. In January 1258 Hülegü's Mongol-Persian army — about 150,000 men, with significant Persian, Christian and Georgian contingents — reached Baghdad. The city had been the capital of the Abbasid Caliphate for more than 500 years and was the cultural and religious heart of Islam: here resided Caliph al-Musta'sim, heir of the Prophet Muhammad; here stood the famous House of Wisdom with the greatest library in the world.
On 10 February 1258 Baghdad surrendered. What followed is called in Muslim chronicles the "catastrophe of Baghdad": the Mongols broke into the city and for a week methodically killed its inhabitants. Modern estimates run from 200,000 to 800,000 dead — in one week. The library of the House of Wisdom was burned — they say the ink from its manuscripts dyed the Tigris black for days. Caliph al-Musta'sim, by Chinggisid taboo, was rolled in a carpet and trampled to death, so that no Mongol sword should touch "the blood of a ruler." The Abbasid caliphate, which had lasted since 750, came to an end. It was an event of such force that the Islamic world remembers it still: in 20th-century Muslim literature "1258" is a cipher for ultimate catastrophe. After Baghdad, Hülegü took Aleppo and Damascus — Syria was about to fall.
Ain Jalut, 3 September 1260
In August 1259, as we have seen, Great Khan Möngke died. The news reached Hülegü in Syria at the beginning of 1260 — and Hülegü, like Batu in 1242, had to return for a kurultai. He left in Syria a small garrison — about 20,000 men — under the Naiman Christian general Kitbuqa. Hülegü returned to Tabriz, going no further than that, because by then the civil war between Kublai and Ariq Böke had already begun.
To the south of Syria stood Egypt — the sultanate of the Mamluks, who had only recently, in 1250, overthrown the last of the Ayyubids and were ruling the country themselves. The young Sultan Qutuz and his general Baibars (a Circassian or Cuman by origin, sold into slavery as a child) understood that this was their chance — while the main Mongol army was far away. Qutuz had the Mongol envoys executed — an unheard-of sign of defiance — and led his army into Syria. On 3 September 1260, in the valley of Ain Jalut (the Spring of Goliath) in Galilee, at the foot of Mount Gilboa, a Mamluk army of about 25,000 and a Mongol army of about 20,000 met in pitched battle. Baibars executed a feigned retreat and lured the Mongols into an ambush. Kitbuqa was killed; his tumen was destroyed entirely. It was the first real defeat of the Mongols in a pitched battle since Genghis Khan's day. Syria was given back to the Mamluks, the Mongols were thrown back beyond the Euphrates — and the border drawn in September 1260 in effect still runs there. Two months later Baibars killed Qutuz and became sultan himself; he and his successors would spend the next 30 years destroying the crusader states of Outremer.
The legacy of the Mongol Empire
The conquests of Genghis Khan and his grandsons cost Eurasia, by various estimates, between 30 and 60 million lives — about 10—15% of the world's population of the time. It was probably the greatest demographic catastrophe of pre-industrial history. Whole cities — Urgench, Khwarazm, Balkh, Baghdad — never recovered their former greatness. The Persian, Chinese and Slavic gene pools were radically changed: today some 16 million men in Eurasia — about one in every 200 men on Earth — carry a Y chromosome which, geneticists estimate, came from a single individual who lived around the 12th—13th centuries in Mongolia. The most likely candidate is Genghis Khan himself. His four sons fathered more than 50 sons between them, and this line bred across Eurasia as no other did.
Paradoxically, this destruction created the Pax Mongolica — two centuries of unprecedented security on the trade routes from Europe to China. A caravan could ride from Caffa in the Crimea to Beijing without a single attack: the great Mongol Yam — a postal-relay system of 50,000 horses and 1,400 stations — guarded everything. In these years Europeans first reached China — Marco Polo (1271—1295), Giovanni del Pian del Carpine (1245—1247), William of Rubruck (1253—1255). In the other direction moved Chinese technology: gunpowder, paper money, printing, the compass — all came to Europe through the Mongol corridor. Silk, spices, Chinese porcelain, Persian astronomy, Arab medicine — all of these the European Renaissance received in good measure through Mongol infrastructure. Genghis Khan's religious tolerance was preserved by his heirs: at Kublai's court in Beijing served Muslims, Nestorian Christians, Buddhists, Confucians, Tibetan lamas and even a Catholic archbishop. It was perhaps the most cosmopolitan court of pre-modern history.
Why it still matters
The Mongol Empire was Globalisation 1.0: the first time in history that a single political power connected the Atlantic with the Pacific. Everything we today call "the world" — the exchange of goods, ideas, diseases, technologies and genes between Europe, Asia and the Near East — in its modern form began precisely in the years 1240—1340, the century of the Pax Mongolica. Venetian, Genoese and Jewish merchants in Sarai and Beijing; Chinese physicians in Tabriz; Persian astronomers at Karakorum; a Frankish archbishop in Khanbaliq. Without that corridor there would probably have been neither a Renaissance in the form it took, nor the European "age of discovery" of the 15th—16th centuries: Columbus was looking not for America but for a shorter route to the China described by Marco Polo. The Black Death — the plague that in 1347, from the Crimean port of Caffa and via Genoese ships, reached Europe and killed a third of its people — also came along the Silk Road that the Mongols had cleared.
In the long historical view the Mongol mark is deeper still. Russia in the form in which it exists — centralised, with an autocrat above the princely clans, with a tributary population and a service aristocracy — is in large part the product of 240 years of the Mongol yoke. Moscow rose as the obedient tax-collector for the khans of Sarai, and when Ivan III in 1480 finally refused to pay, he in effect inherited the Golden Horde's system. Iran today is largely shaped by the Ilkhanid empire (the descendants of Hülegü), who at the end of the 13th century became Muslim and created the Persian cultural synthesis we know as "classical Iran." China in its modern borders — from Manchuria to Tibet and Xinjiang — is the geography drawn by the Mongol Yuan dynasty of 1271—1368. All of Eurasia between the Baltic and the Yellow Sea, the Urals and the Himalayas, is in a certain sense a geopolitical product of Genghis Khan, who around 1206 decided that the Borjigin clan should rule "all that the Eternal Blue Sky sees." And, strange to say, it has been seeing for 800 years now.