User:AirshipJungleman29/Genghis Khan

Genghis Khan (born Temüjin; c. 1162 — 25 August 1227), also known as Chinggis Khan, was the founder and first khagan of the Mongol Empire, which later became the largest contiguous land empire in history. Having spent the majority of his life uniting the Mongol tribes, he launched a series of military campaigns which conquered large parts of China and Central Asia.

Born between 1155 and 1167 and given the name of Temüjin, he was the oldest child of Yesugei, a Mongol chieftain of the Borjigin clan, and his wife Hoelun of the Olkhonuds. Yesugei died when Temüjin was eight, and his family was abandoned by their tribe in the Mongol steppe. Temüjin gradually built up a small following, and allied with Jamukha and Toghrul, two other Mongol chieftains, in campaigns against other tribes. Due to the erratic nature of the sources, this period of Temüjin's life is uncertain; he may have spent time as a servant of the Chinese Jin dynasty. The alliances with Jamukha and Toghrul failed completely in the early 13th century, but Temüjin was able to defeat both and claim sole rulership of the Mongol tribes. He formally adopted the name Genghis Khan at a kurultai in 1206.

With the tribes fully united under his command, Genghis Khan expanded eastwards. He vassalised the smaller Western Xia state by 1211 and then invaded the Jin state in northern China; the Mongols pillaged the North China Plain so thoroughly that the Jin emperor was forced to abandon the northern half of his kingdom in 1214. Mongol forces annexed the Qara Khitai khanate in 1218, allowing Genghis Khan to lead a massive invasion of the neighbouring Khwarazmian Empire the following year. The invading Mongols toppled the Khwarazmian state and devastated the regions of Transoxania and Khorasan, killing and enslaving millions of people. Genghis Khan died in 1227 while besieging the rebellious Western Xia; his third son and heir Ögedei succeeded to the throne two years later.

The Mongol campaigns started by Genghis Khan saw widespread destruction and millions of deaths in the areas they conquered. The Mongol army he built was renowned for its flexibility, discipline, and organisation, while his empire established upon meritocratic principles. Genghis Khan also codified the Mongol legal system, promoted religious tolerance, and encouraged pan-Eurasian trade through the Pax Mongolica. He is revered and honored in modern Mongolia as a symbol of national identity and a central figure of Mongolian culture.

Name and titles
There is no standardised system of transliterating original Mongolian names into English; many different systems continue to be in use today, resulting in modern spellings that often differ considerably from the original pronunciation. Ultimately, the honorific most commonly spelt Genghis derives from the autochthonous Mongolian , most closely represented in English by the spelling Čhinggis. From this origin derived the Chinese and the ; Čəngīz H̱ān. As Arabic lacks a similar sound to "Č", writers using the language transliterated the name to Şıñğıs xan or Cənġīz H̱ān. In modern English, common spellings include Chinggis, Chingis, Jinghis, and Jengiz, in addition to the dominant Genghis, which was introduced by 18th-century French scholars who misread the original texts. His birth name  is most commonly spelt Temüjin in English, although Temuchin is also sometimes used.

When Genghis' grandson Kublai Khan established the Yuan dynasty in 1271, he bestowed the temple name Taizu (, meaning "Supreme Progenitor") and the posthumous name Shengwu huangdi (, meaning "Holy-Martial Emperor") upon his grandfather. Külüg Khan later expanded this title into Fatian Qiyun Shengwu Huangdi (, meaning "Interpreter of the Heavenly Law, Initiator of the Good Fortune, Holy-Martial Emperor").

Birth and early life
The year of Temüjin's birth is disputed, as historians favour different dates: 1155, 1162 or 1167. Some traditions place his birth in the Year of the Pig, which was either 1155 or 1167. While a dating to 1155 is supported by the writings of both Rashid al-Din and the Chinese diplomat Zhao Hong, other major sources such as the Yuán Shǐ and the Shengwu favour the year 1162. The 1167 dating, favoured by Paul Pelliot, is derived from a minor source—a text of the Yuan artist Yang Weizhen—but is far more compatible with the events of Genghis Khan's life. For example, an 1155 placement implies that he did not have children until after the age of thirty and continued actively campaigning into his seventh decade. Nevertheless, Pelliot was not certain of the accuracy of his theory, which remains controversial; the historian Paul Ratchnevsky notes that Temüjin himself may not have known the truth. The location of Temüjin's birth is similarly debated: the Secret History records his birthplace as Delüün Boldog on the Onon River, but this has been placed at either Dadal in Khentii Province or in southern Agin-Buryat Okrug, Russia.

Temüjin was born into the Borjigin clan to Yesügei, a chieftain descended from the revered warlord Bodonchar Munkhag, and his principal wife Hoelun, originally of the Olkhonud clan, whom Yesügei had abducted from her Merkit bridegroom Chiledu. The origin of his birth-name is contested: the earliest traditions hold that his father had just returned from an successful expedition against the Tatars with a captive named Temüchin-uge, after whom he named the newborn in celebration of his victory, while later traditions highlight the root temür (meaning iron), also present in the names of two of his siblings, and connect to theories that Temüjin means "blacksmith". Several legends surround Temüjin's birth. The most prominent is that of a blood clot he clutched in his hand as he was born, an Asian folklorish motif which indicated the child would be a warrior. Others claimed that Hoelun was impregnated by a ray of light which announced the child's destiny, a legend which echoed that of the mythical ancestor Alan Gua. Yesügei and Hoelun had three younger sons after Temüjin: Qasar, Hachiun, and Temüge, as well as one daughter, Temülen. Temüjin also had two half-brothers, Behter and Belgutei, from Yesügei's second wife Sochigel, whose identity is uncertain. The siblings grew up at Yesugei's main camp on the banks of the Onon, where they learned how to ride a horse and shoot a bow.

When Temüjin was eight years old, Yesügei decided to betroth him to a suitable girl; he took his heir to the pastures of the prestigious Onggirat tribe, which Hoelun had been born into, and arranged a marriage between Temüjin and Börte, the daughter of an Onggirat chieftain named Dei Sechen. As the betrothal meant Yesügei would gain a powerful ally, and as Börte commanded a high bride price, Dei Sechen held the stronger negotiating position, and demanded that Temüjin remain in his household to work off his future bride's dowry. While riding homewards alone, having accepted this condition, Yesügei requested a meal from a band of Tatars he encountered, relying on the steppe tradition of hospitality to strangers. However, the Tatars recognised their old enemy, and slipped poison into his food. Yesügei gradually sickened but managed to return home; close to death, he requested a trusted retainer called Münglig to retrieve Temüjin from the Onggirat. He died soon after.

Adolescence
Yesügei's death shattered the unity of his people. As Temüjin was only around ten, and Behter around two years older, neither was considered old enough to rule. Led by the widows of Ambaghai, a previous Mongol khan, a Tayichiud faction excluded Hoelun from the ancestor worship ceremonies which followed a ruler's death and soon abandoned the camp. The Secret History relates that the entire Borjigin clan followed, despite Hoelun's attempts to shame them into staying with her family. Rashid al-Din and the Shengwu qinzheng lu however imply that Yesügei's brothers stood by the widow. It is possible that Hoelun may have refused to join in levirate marriage with one, or that the author of the Secret History dramatised the situation. All the sources agree that most of Yesügei's people renounced his family in favour of the Tayichiuds and that Hoelun's family were reduced to a much harsher life. Taking up a traditional hunter-gatherer lifestyle, they collected roots and nuts, hunted for small animals, and caught fish.

Tensions developed as the children grew older. Both Temüjin and Behter had claims to be their father's heir: although Temüjin was the child of Yesügei's chief wife, Behter was at least two years his senior. There was even the possiblity that, as permitted under levirate law, Behter could marry Hoelun upon attaining his majority and become Temüjin's stepfather. As the friction, excarbated by regular disputes over the division of hunting spoils, intensified, Temüjin and his younger brother Qasar ambushed and killed Behter. This taboo act was omitted from the official chronicles but not from the Secret History, which recounts that Hoelun angrily reprimanded her sons. Behter's younger full-brother Belgutei did not seek vengeance, and became one of Temüjin's highest-ranking followers alongside Qasar. Around this time, Temüjin developed a close friendship with Jamukha, another boy of aristocratic descent; the Secret History notes that they exchanged knucklebones and arrows as gifts and swore the anda pact—the traditional oath of Mongol blood brothers–at the age of eleven.

As the family lacked allies, Temüjin was likely taken prisoner on multiple occasions. The Secret History relates one such occasion when he was captured by the Tayichiuds who had abandoned him after his father's death. Escaping during a Tayichiud feast, he hid first in the River Onon and then in the tent of Sorkan-Shira, a man who had seen him in the river and not raised the alarm; Sorkan-Shira sheltered Temüjin for three days at great personal risk before allowing him to escape. Temüjin was assisted on another occasion by an adolescent named Bo'orchu who aided him in retrieving stolen horses. Soon afterwards, Bo'orchu joined Temüjin's camp as his first nökor (personal companion; nökod). These incidents are indicative of the emphasis the author of Secret History put on personal charisma.

Early campaigns
Accompanied by Belgutei, Temüjin returned to Dei Sechen to marry Börte when he became an adult at fifteen. The Onggirat chieftain, delighted to see the son-in-law he feared had been lost, immediately consented to the marriage, and accompanied the newlyweds back to Temüjin's camp; his wife Čotan presented Hoelun with a black sable cloak, a sign of great wealth. Seeking a patron, he then chose to approach Toghrul, khan of the Kerait tribe, who had fought alongside Yesügei and sworn the anda pact with him. Toghrul ruled hundreds of miles and commanded up to 20,000 warriors, but he was suspicious of the loyalty of his chief followers and, after being presented with the sable cloak, he welcomed Temüjin into his protection. The two grew close, and Temüjin began to build a following, as nökod such as Jelme entered into his service.

Soon afterwards, seeking revenge for Yesügei's abduction of Hoelun, around 300 Merkits raided Temüjin's camp. While Temüjin and his brothers were able to hide on Burkhan Khaldun, Börte and Sochigel were abducted. In accordance with levirate law, Börte was given to Chilger, younger brother of Chiledu. Temüjin appealed for aid from Toghrul and his childhood anda Jamukha, who had risen to become chief of the Jadaran tribe. Both chiefs were willing to field armies of 20,000 warriors, and with Jamukha in command, the campaign was soon won. A now-pregnant Börte was recovered successfully and soon gave birth to a son, Jochi; although Temüjin raised him as his own, questions over his true paternity followed Jochi throughout his life. This is narrated in the Secret History and contrasts with Rashid al-Din's account, which protects the family's reputation by removing any hint of illegitimacy.

Temüjin and Jamukha camped together for a year and a half, during which, according to the Secret History, they reforged their anda pact, even sleeping together under one blanket. Traditionally seen as a bond solely of friendship, as presented in the source, Ratchnevsky has questioned if Temüjin was actually serving as Jamukha's nökor, in return for the assistance with the Merkits. Tensions arose and the two leaders parted, ostensibly on account of a cryptic remark made by Jamukha on the subject of camping; scholarly analysis has focused on the active role of Börte in this separation, and whether her ambitions may have outweighed Temüjin's own. In any case, the major trial rulers remained with Jamukha, but forty-one named leaders joined Temüjin along with many commoners: these included Subutai and others of the Uriankhai, the Barulas, the Olkhonuds, and many more.

Temüjin was soon acclaimed by his close followers as khan of the Mongols. Toghrul was pleased at his vassal's elevation but Jamukha was resentful. Tensions escalated into open hostility, and in around 1187 the two leaders clashed in battle at Dalan Baljut: the two forces were evenly matched but Temüjin suffered a clear defeat. Later chroniclers including Rashid al-Din instead state that he was victorious but their accounts contradict themselves and each other.

Modern historians consider it very likely that Temüjin spent a large portion of the decade following the clash at Dalan Baljut as a servant of the Chinese Jin dynasty. Zhao Hong, a 1221 ambassador from the Song dynasty, recorded that the future Genghis Khan spent several years as a slave of the Jin. Traditionally seen as an expression of Chinese arrogance, the statement is now thought to be based in fact, especially as no other source convincingly explains Temüjin's activities between Dalan Baljut and c. 1195. Taking refuge across the border was a common practice both for disaffected steppe leaders and disgraced Chinese officials. Temüjin's reemergence c. 1195 having retained significant power indicates that he probably profited in the service of the Jin. As he would later go on to overthrow that state, such an episode, detrimental to Mongol prestige, was omittted from all their sources. Zhao Hong was bound by no such taboos.

Defeating rivals
The sources do not agree on the events of Temüjin's return to the steppe. In early summer 1196, he participated in a joint campaign with the Jin against the Tatars, who had begun to exert their power; as a reward, the Jin awarded him the honorific cha-ut kuri. At around the same time, he assisted Toghrul with reclaiming the lordship of the Kereit, which had been taken by a family member with the support of the powerful Naiman tribe. Toghrul was given the title of Ong Khan by the Jin, traditionally as a reward for his support during the Tatar campaign. In fact, Toghrul may not have participated in the warfare, and the title was only thus given as a pacificatory gesture. At all events, the actions of 1196 fundamentally changed Temüjin's position in the steppe—he was now Toghrul's equal ally, rather than his junior vassal.

Jamukha behaved poorly following his victory at Dalan Baljut, allegedly beheading enemy leaders and humiliating their corpses, or boiling seventy prisoners alive. As a consequence, a number of disaffected followers, including Yesügei's nökor Münglig and his sons, defected to Temüjin. Temüjin was able to subdue the disobedient Jurkin tribe, who had previously offended him at a feast and had refused to participate in the Tatar campaign: after eliminating their leaders, he had Belgutei symbolically break a leading Jurkin's back in a staged wrestling match in retribution. This latter incident, which contravened Mongol customs of justice, was only noted by the author of the Secret History, who openly disapproved. These events occurred c. 1197.

During the following years, Temüjin and Toghrul campaigned separately and together against the Merkits, the Naimans, and the Tatars. In around 1201, a collection of dissatisfied tribes including the Onggirat, the Tayichiud, and the Tatars, swore to break the domination of the Borjigin-Kereit alliance, electing Jamukha as gurkhan and their leader. After some initial successes, this loose confederation was routed at Yedi Qunan, and Jamukha was forced to beg for Toghrul's clemency. Desiring complete supremacy in eastern Mongolia, Temüjin defeated first the Tayichiud and then, in 1202, the Tatars; after both campaigns, he executed the clan leaders and took the remaining warriors into his service. These included Sorkan-Shira, who had come to his aid previously, and a young warrior named Jebe, who, by killing Temüjin's horse and refusing to hide that fact, had displayed military skill and personal courage.

The absorption of the Tatars left three military powers in the steppe: the Naimans in the west, the Mongols in the east, and the Kereit in between. Seeking to cement his position, Temüjin proposed that his son Jochi marry one of Toghrul's daughters. Led by Toghrul's son Senggum, the Kereit elite believed the proposal to be an attempt to gain control over their tribe, while the doubts over Jochi's parentage would have offended them further. In addition, Jamukha drew attention to the threat Temüjin posed to the traditional steppe aristocracy. Yielding eventually to these demands, Toghrul attempted to lure his vassal into an ambush, but his plans were overheard by two herdsmen. Temüjin was able to gather some of his forces, but was soundly defeated at the Qalaqaljid Sands.

Temüjin retreated southeast to Baljuna, an unidentified lake or river, where he waited for his scattered forces to regroup: Bo'orchu had lost his horse and was forced to flee on foot, while Temüjin's badly wounded son Ögedei had been transported and tended to by Borokhula, a leading warrior. He called in every possible ally, including the Onggirat and Muslim merchants who provided his camp with sheep. According to many sources but not the Secret History, he also swore an oath of loyalty to his faithful followers; this oath, later known as the Baljuna Covenant, gave those present exclusivity and great prestige. A ruse de guerre involving Qasar allowed the Mongols to catch the Kereit unawares at the Jej'er Heights, but though the ensuing battle still lasted three days, it ended in a decisive victory for Temüjin. Toghrul and Senggum were both forced to flee, and while the latter escaped southwards, Toghrul was killed by a Naiman who did not recognise him. Temüjin sealed his victory by absorbing the Kereit elite into his own tribe: he took the princess Ibaqa to be his own wife, and gave her sister Sorghaghtani and niece Doquz to his youngest son Tolui.

The ranks of the Naimans had been swelled by the arrival of Jamukha and others defeated by the Mongols, and they soon prepared for war. Temüjin was informed of these events by Alaqush, the sympathetic ruler of the Ongud tribe. In the Battle of Chakirmaut, which occurred in May 1204 in the Altai Mountains, the Naimans were decisively defeated: their leader Tayang Khan was killed, and his son Kuchlug was forced to flee west. The Merkits would be decimated later that year, while Jamukha, who had abandoned the Naimans at Chakirmaut, was betrayed to Temüjin by companions who were executed for their lack of loyalty. According to the Secret History, Jamukha convinced his childhood anda to execute him honourably; other accounts state that he was killed by dismemberment.

Kurultai of 1206 and reforms
Now sole ruler in the steppe, Temüjin held a kurultai at the source of the Onon River in 1206. Here, he formally adopted the title Genghis Khan, the etymology and meaning of which has been much debated. Some commentators hold that the title had no meaning, simply representing Temüjin's eschewment of the traditional "gurkhan" title, which had been accorded to Jamukha and was thus of lesser worth. Another theory suggests that the word "Genghis" bears connotations of strength, firmness, hardness, or righteousness. A third hypothesis proposes that the title is related to the Turkic "tängiz", meaning "sea" or "ocean"; the title "Genghis Khan" would mean "master of the ocean", and as the ocean was believed to surround the earth, the title ultimately implied "Universal Ruler".

Having attained control over one million people and over fifteen million animals, Genghis Khan began what May has termed a "social revolution".. As traditional tribal systems had primarily evolved to benefit small clans and families, they were unsuitable as the foundations for larger states and had been the downfall of previous steppe confederations. Aware that a different organisational structure was required to optimise his new nation, Genghis began a series of administrative reforms designed to suppress the power of tribal loyalties and to replace them with unconditional loyalty to the khan and the ruling family. As most of the traditional tribal leaders had been killed during his rise to power, Genghis was able to reconstruct the Mongol social hierarchy in his favour. The highest societal tier was occupied solely by the families of the Khan and his brothers, who became known as the altan uruq (lit. "Golden Family") or chaghan yasun (lit.  "white bone"); underneath them came the qara yasun (lit.  "black bone"; sometimes qarachu), composed of the surviving pre-empire aristocracy and the most important of the new families.

To break any concept of tribal loyalty, the entirety of Mongol society was reorganised into a decimal system of military organisation. Every man between the age of fifteen and seventy was conscripted into a minqan ( minkad), a unit of a thousand soldiers, which was further subdivided into units of hundreds (jaghun, jaghat) and tens (arban,  arbat). The units also encompassed each man's household, meaning that each military minqan was supported by a minqan of households in a defined military–industrial complex. Each minqan operated as both political and social units, while the warriors of defeated tribes were dispersed to different minqad so that they could not rebel as a single body. This was intended to ensure the disappearance of old tribal identities, replacing them with loyalty to the Yeke Mongol Ulus (lit. "Great Mongol State") and to commanders who had gained their rank through meritocratic skill and loyalty to the khan. This particular reformation proved extremely effective—even after the division of the Mongol Empire, fragmentation never happened along tribal lines. Instead, the Borjigin Genghisids continued to reign unchallenged, in some cases until as late as the 1700s, and even powerful non-imperial dynasts such as Timur and Edigu were compelled to rule from behind a Genghisid puppet ruler.

Genghis' senior nökod were appointed to the highest ranks and received the greatest honours. Bo'orchu and Muqali were each given ten thousand men (tumen, tumed) to lead as commanders of the right and left wings of the army respectively. The other nökod were given commands of one of the ninety-five minkad. Many of these men were born to low social status: Ratchnevsky cites Jelme and Subutai, the sons of blacksmiths, in addition to a carpenter, a shepherd, and even the two herdsmen who had warned Temüjin of Toghrul's plans in 1203. As a special privilege, Genghis allowed certain loyal commanders to retain the tribal identities of their units. Alakush of the Ongud was allowed to retain five thousand warriors of his tribe because his son had married Genghis' daughter Alakhai Bekhi, while Chigu and Alchi of the Onggirat, as husband to Genghis' sister Temülen and brother to Börte respectively, were granted three minkad each. These large exemptions were bestowed because of existing quda (lit. "marriage alliance") pacts.

A key tool which underpinned these reforms was the expansion of the keshig (lit. "bodyguard"). After Temüjin's defeat of Toghrul in 1203, he had appropriated this Kereit institution in a minor form, but at the 1206 kurultai its numbers were greatly expanded, from 1,150 to 10,000 men. The keshig was not only the khan's bodyguard, but his household staff, a military academy, a guarantor of loyalty, and the basis of governmental administration. All the warriors in this elite corps, divided into an 8,000-strong day guard and two minqad of night guards and quiver bearers, were brothers or sons of military commanders, and were essentially hostages. The keshigten (lit. "keshig members") nevertheless received special privileges and direct access to the khan, whom they would serve in all respects during both peace and war, and who in return would evaluate their capabilities and their potential to govern or command.

Consolidation of power and Xi Xia campaign (1206–1210)
From 1206 to 1209, Genghis Khan was predominantly devoted to consolidating and maintaining his new nation. He faced a challenge from Kokechu, the son of Münglig, the trusted retainer of Yesügei to whom Genghis had given his mother Hoelun in marriage. Kokechu was the shaman who had proclaimed Temüjin as Genghis Khan who had taken the Tengrist title "Teb Tenggeri" (lit. "Wholly Heavenly") on account of his sorcery; he was very influential among the Mongol commoners, and sought to divide the imperial family. Genghis' oldest sibling Qasar was the first of Kokechu's targets—always distrusted by his brother, he was humiliated and almost imprisoned on false charges before Hoelun intervened by publicly reprimanding her eldest son. Nevertheless, Kokechu's power steadily increased, and when Genghis' youngest brother Temüge attempted to intervene he too was publicly shamed. On this occasion it was Börte who saw the threat Kokechu posed—he could potentially turn the fledgling empire into a prophet-dominated state like the Rashidun Caliphate—and warned Genghis, who still superstitiously revered the shaman. He relented, allowing Temüge to assassinate Kokechu, and essentially usurped the shaman's position as the Mongols' highest spiritual authority.

During these years, the Mongols also imposed their control on surrounding areas. Genghis dispatched Jochi northwards in 1207 to subjugate the Hoi-yin Irgen, a collection of tribes on the edge of the Siberian taiga, and, having secured a marriage alliance with the Oirats and defeated the Yenisei Kyrgyz, took control of the region's grain trade, fur trade, and gold mines. Mongol armies also rode westwards, defeating the Naimans-Merkit alliance on the River Irtysh in late 1208—their khan was killed and Kuchlug fled into Central Asia. Led by Barchuk, the Uighurs freed themselves from the suzerainty of the Qara-Khitai and pledged themselves to Genghis in 1211, as the first sedentary society to submit to the Mongols.

The Mongols had started raiding the border settlements of the Tangut-Xi Xia kingdom in 1205, ostensibly in retaliation for allowing Senggum, Toghrul's son, refuge; a more prosaic explanation is that the Mongol economy, ruined by civil war, needed an influx of fresh goods and livestock. Most Xia troops were stationed along the southern and western borders of the kingdom to guard against attacks from the Song and Jin dynasties respectively, while its northern border relied only on the Gobi desert for protection, unlike the Jin's which was strongly fortified. After another raid in 1207 sacked the fortress of Wulahai, Genghis decided to personally lead a full-scale invasion in 1209. Wulahai was captured again in May and the Mongols advanced on the capital Zhongxing (modern-day Yinchuan) but suffered a reverse against a Tangut army. After a two-month stalemate, Genghis broke the deadlock with a successfully-executed feigned retreat. Although Zhongxing was now mostly undefended, lacking any siege equipment better than crude battering rams, the Mongols were unable to progress the siege. Genghis' innovative attempt to redirect the Yellow River into the city with a dam initially worked, but the poorly-constructed earthworks broke—possibly breached by the Xia—in January 2010 and the Mongol camp was flooded, forcing them to retreat. A peace treaty was soon formalized: the Tangut emperor Xiangzong submitted and handed over tribute, including his daughter Chaka, in exchange for the Mongol withdrawal.

Campaign against the Jin (1211–1215)
Wanyan Yongji usurped the Jin throne in 1209. He had previously served on the steppe frontier, and Genghis greatly disliked him; he also declined to aid the Xia against the Mongols. When asked to submit and pay the annual tribute to Yongji in 1210, Genghis instead mocked the emperor, spat, and rode away from the Jin envoy—a challenge which meant war. He had learned in 1206 of the insecurities within the nominally powerful Jin state, and had made preparations since then to invade, despite the possibility of his 75,000 Mongol troops being outnumbered eight-to-one by 600,000 Jin soldiers. Genghis had two aims: to take vengeance for past wrongs committed by the Jin, foremost among which was the death of Ambaghai Khan in the mid-12th century; and to win the vast amounts of plunder his troops and vassals expected.

Having called for a kurultai in March 1211, Genghis launched his invasion of Jin China in May, reaching the outer Jin defence ring the following month. These border fortifications were guarded by the Ongud tribe, who were friendly to the Mongols—through his daughter Alakhai Beki, Genghis held a quda alliance with their leader Alaqush—and allowed them to pass without difficulty. The three-pronged campaign—termed "a vast chevauchée by the historian James Waterson—aimed both to plunder and burn a vast area of north China and Manchuria, so the ruling Jin would be deprived of supplies and popular legitimacy, and to secure the mountain passes which allowed access to the North China Plain. The Jin lost numerous towns and were hindered by a series of defections, the most prominent that of the Khitan Shimo Ming'an, whose betrayal led directly to Muqali's decisive victory at the Battle of Huan'erzhui in autumn 1211. The campaign was halted in 1212 when Genghis was wounded by an arrow during the siege of Xijing; the Mongols had achieved all their objectives, with the Jin's slow-moving defensive strategy unable to match the organisation of the Mongol horse archers. Following the failure at Datong, Genghis set up a corps of siege engineers, which recruited 500 Jin experts over the next two years.

Although the Juyong Pass defences had been strongly reinforced by the time the conflict resumed in 1213, a Mongol detachment led by Jebe managed to infiltrate the pass and surprise the elite Jin defenders, opening the road to the Jin capital Zhongdu (modern-day Beijing). The Jin administration began to disintegrate: after the Khitans had entered open rebellion, Hushahu, the commander of the forces at Xijing, abandoned his post and staged a coup in Zhongdu, killing Yongji and installing his own puppet ruler, Xuanzong. This governmental breakdown was fortunate for Genghis' forces—emboldened by their victories, they had seriously overreached and lost their initiative. Unable to do more than sit before Zhongdu's fortifications while his army suffered from an epidemic and famine—the Mongols are reported to have resorted to cannibalism—Genghis opened peace negotiations, despite his commanders' militarism. He secured tribute, including 3,000 horses, 500 slaves, a Jin princess, and massive amounts of gold and silk, before breaking the siege in spring 1214 and setting off homewards in May 1214.

With the northern Jin lands ravaged by plague and the Mongols, Xuanzong made a drastic decision: he moved the capital and imperial court 600 km southwards to Kaifeng. Genghis saw this move as a betrayal of the peace treaty and immediately prepared to return, even though he had been away from home for three years. According to Christopher Atwood, it was only at this juncture that Genghis decided to fully conquer northern China. Muqali captured numerous towns in Liaodong during winter 1214–15, and although the despairing inhabitants of Zhongdu surrendered to Genghis on 31 May 1215, the city was thoroughly sacked and looted. When Genghis returned to Mongolia in early 1216, Muqali was left in command in China; he waged a brutal but effective campaign against the unstable Jin until his death in 1223.

Defeating rebellions and Qara Khitai (1216–1218)
In 1207, Genghis had appointed a man named Qorchi as governor of the subdued Hoi-yin Irgen tribes. Appointed not for his talents but for prior services rendered, Qorchi was a poor choice, and his habit of taking too many concubines for his harem led the tribes to rebel and take him prisoner in early 1216. Boroqul, one of Genghis' highest-ranking nökod, was ambushed and killed the following year. The khan was livid at the loss of his close friend and prepared to personally lead a retaliatory campaign; eventually dissuaded from this course, he dispatched his eldest son Jochi and a Dörbet commander. They managed to surprise and defeat the rebels, securing control over this economically important region.

Kuchlug, the Naiman prince who had been defeated in 1204, had usurped the throne of the Central Asian Qara Khitai dynasty between 1211 and 1213. He was a greedy and arbitrary ruler who may have earned the enmity of the native Islamic populace whom he attempted to forcibly convert to Buddhism. Genghis sensed that Kuchlug might be a potential threat to his empire, and Jebe was sent with an army of 20,000 cavalry to Kashgar; he undermined Kuchlug's rule by emphasising the Mongol policies of religious tolerance and gained the loyalty of the local elite. Kuchlug was forced to flee southwards to the Pamir Mountains, but was captured by local hunters. Decapitated by the Mongols, his corpse was paraded through Qara Khitai, and Jebe proclaimed the end of religious persecution in the region.

Invasion of the Khwarazmian Empire
Genghis had now attained complete control of the eastern portion of the Silk Road, and his territory bordered that of the Khwarazmian Empire, which ruled over much of Central Asia, Persia and Afghanistan. Merchants from both sides were eager to restart trading—the Khwarazmian ruler Muhammad II dispatched an envoy shortly after the Mongol capture of Zhongdu, while Genghis instructed the ortoq, the Mongol trading partners, to obtain the high-quality textiles and steel of Central and Western Asia, the trade having halted during Kuchlug's rule. Many members of the altan uruq invested in one particular caravan of 450 merchants which set off to Khwarazmia in 1218 with a massive quantity of goods. Muhammad had however grown suspicious of Genghis' intentions, and when Inalchuq, the governor of the Khwarazmian border town of Otrar, decided to halt the caravan, massacre the merchants on grounds of espionage, and seize the goods, the Khwarazmshah either supported Inalchuq or turned a blind eye. A Mongol ambassador was sent with two companions to avert war, but he was killed and his companions humiliated. The killing of an envoy infuriated Genghis, who resolved to leave Muqali with a small force in North China and invade Khwarazmia with most of his army in late 1219.

Muhammad's empire was large but disunited: he ruled alongside his mother Terken Khatun in what Peter Golden termed "an uneasy diarchy", while the Khwarazmian nobility and populace were discontented with his warring and centralization of government. For these reasons and others he declined to meet the Mongols in the field, instead garrisoning his unruly troops in his major cities. This allowed the lightly-armoured, highly mobile Mongol armies uncontested superiority outside city walls. Otrar was besieged in autumn 1219—the siege dragged on for five months, but in February 1220 the city fell and Inalchuq was executed. Genghis had meanwhile divided his forces. Leaving his sons Chagatai and Ogedei besieging the city, he had sent Jochi northwards down the Syr Darya river and another force southwards into central Transoxiana, while he and Tolui took the main Mongol army across the Kyzylkum Desert, surprising the garrison of Bukhara in a pincer movement.

Bukhara's citadel was captured in February 1220 and Genghis moved against Muhammad's residence Samarkand, which fell the following month. Bewildered by the speed of the Mongol conquests, Muhammad fled from Balkh, closely followed by Jebe and Subutai; the two generals pursued the Khwarazmshah until his death from dysentry on a Caspian Sea island in winter 1220/21. Before his death, he nominated his eldest son Jalal al-Din as his successor. Jebe and Subutai then set out on a massive 7500 km expedition around the Caspian Sea. Later called The Great Raid, this lasted four years and saw the Mongols come into contact with medieval Europe for the first time. Meanwhile, the Khwarazmian capital of Gurganj was being besieged by Genghis' three eldest sons; a long siege ended in spring 1221 amid brutal urban conflict. Jalal al-Din moved southwards to Afghanistan, gathering forces on the way and defeating a Mongol unit under the command of Shigi Qutuqu, Genghis' adopted son, in the Battle of Parwan. Jalal was weakened by arguments among his commanders, and losing decisively at the Battle of the Indus in November 1221, he was compelled to swim across the river into India.

Genghis' youngest son Tolui was concurrently conducting a brutal campaign in the regions of Khorasan. Every city that resisted was destroyed in a programme of concentrated devastation—Nishapur, Merv and Herat, three of the largest and wealthiest cities in the world, were all annihilated. This campaign established Genghis' lasting image as a ruthless, inhumane conqueror. Persian historians placed the death toll from the three sieges at over 5.7 million—numbers regarded as grossly exaggerated by most modern scholars. Nevertheless, even a total death toll of 1.25 million, as estimated by John Man, would have been a demographic catastrophe.

Return to China and final campaign
Genghis abruptly halted his Central Asian campaigns in 1221. Initially aiming to return via India, Genghis realised that the heat and humidity of the South Asian climate impeded his army's skills, while the omens were additionally unfavourable. Although the Mongols spent much of 1222 repeatedly overcoming rebellions in Khorasan, they withdrew completely from the region to avoid overextending themselves, setting their new frontier on the Amu Darya river. During his lengthy return journey, Genghis prepared a new administrative division which would govern the conquered territories, appointing darughachi (comissioners, lit. "those who press the seal") and basqaq (local officials) to manage the region back to normalcy. He also summoned and spoke with the Daoist patriarch Changchun in the Hindu Kush. The khan listened attentively to Changchun's teachings and granted his followers numerous privileges, including tax exemptions and authority over all monks throughout the empire—a grant which the Daoists would later use to try to gain superiority over Buddhism.

The usual reason given for the halting of the campaign is that the Western Xia, having declined to provide auxiliaries for the 1219 invasion, had additionally disobeyed Muqali in his campaign against the remaining Jin in Shaanxi province. May has disputed this, arguing that the Xia fought in concert with Muqali until his death in 1223, when, frustrated by Mongol control and sensing an opportunity with Genghis in Central Asia, they ceased fighting. In either case, Genghis initially attempted to resolve the situation diplomatically, but when the Xia elite failed to come to an agreement on the hostages they were to send to the Mongols, he lost patience. Returning to Mongolia in early 1225, he spent the year in preparation for the campaign, which began in the first months of 1226 with the capture of Khara-Khoto on the Xia's western border.

The invasion proceded apace. Genghis ordered that the cities of the Gansu Corridor be sacked one by one, granting clemency only to a few. Having crossed the Yellow River in autumn, the Mongols besieged present-day Lingwu, located just 30 km south of the Xia capital Zhongxing in November. On December 4, Genghis decisively defeated a Xia relief army; the khan left the siege of the defenceless capital to his generals and moved southwards with Subutai to plunder and secure Jin territories.

Death and burial
Genghis, who had suffered a fall from his horse while hunting in the winter, became increasingly ill during the following months. This slowed the siege's progress, as his sons and commanders urged him to end the campaign and return to Mongolia to recover, arguing that the urban-bound Xia would still be there another year. Incensed by insults from Xia's leading commander, Genghis insisted that the siege be continued. He died in August 1227, but his death was kept a closely guarded secret and Zhongxing, unaware, fell the following month. The city was put to the sword and its population was treated with extreme savagery—the Xia civilisation was essentially extinguished in what Man described as "very successful ethnocide". The exact nature of the khan's death has been the subject of intense speculation. Rashid al-Din and the Yuán Shǐ mention he suffered from an illness—possibly malaria, typhus, or bubonic plague. Marco Polo attests that he was shot by an arrow during a siege, while Carpini reports that Genghis was struck by lightning. Legends sprang up around the event—the most famous recounts how the beautiful Gurbelchin, formerly wife to the Xia emperor, castrated Genghis with a concealed dagger during sexual intercourse.

After his death, Genghis was transported back to Mongolia and buried on or near the sacred Burkhan Khaldun peak in the Khentii Mountains, on a site he had personally chosen years before. Specific details of the funeral procession and burial were not made public knowledge; the mountain, declared ikh khorig (lit. "Great Taboo"; i.e. prohibited zone), was off-limits to all but its Uriankhai guard. When Ogedei acceded to the throne in 1229, the grave was honoured with three days of offerings and the sacrifice of thirty maidens. Ratchnevsky theorises that the Mongols, who had no knowledge of embalming techniques, may have buried the khan in the Ordos to avoid his body decomposing in the summer heat; Atwood emphatically rejects this hypothesis.

Succession
At some point, Genghis had...