Early organization manuscript|alt=Illustration of a crowned man on a throne, surrounded by retainers. At a
kurultai (assembly) in 1206, the shaman Teb Tenggeri proclaimed Temüjin khan of the "Great Mongol Nation" (). Here Temüjin assumed the title Genghis Khan, the meaning of which is not certain. He then instituted a series of institutional reforms which constituted, according to the historian Timothy May, a "social revolution". Genghis reconstituted steppe society by redistributing the tribal peoples into "a military-industrial complex" (May) based on the
decimal system. His favoured followers—some of whom were of low birth—were allocated to command ninety-five ( ), or units of a thousand, which were in turn subdivided into hundreds and tens. Compared to the units he gave to his loyal companions, those assigned to his own family members were relatively few. He proclaimed a new code of law of the empire,
Ikh Zasag or
Yassa; later he expanded it to cover much of the everyday life and political affairs of the nomads. He forbade the selling of women, theft, fighting among the Mongols, and the hunting of animals during the breeding season. He appointed his stepbrother
Shikhikhutug as supreme judge (jarughachi), ordering him to keep records of the empire. In addition to laws regarding family, food, and the army, Genghis decreed religious freedom and supported domestic and international trade. He exempted the poor and the clergy from taxation. He also encouraged literacy and the adaptation of the
Uyghur script into what would become the
Mongolian script of the empire, ordering the
Uyghur Tata-tonga, who had previously served the khan of
Naimans, to instruct his sons.
Push into Central Asia Genghis quickly came into conflict with the Jin dynasty of the Jurchens and the
Western Xia of the
Tanguts in northern China. He also had to deal with two other powers,
Tibet and
Qara Khitai. Before his death, Genghis Khan divided his empire among his sons and immediate family, making the Empire the joint property of the entire imperial family who, along with the Mongol aristocracy, constituted the ruling class. Genghis arranged for the Chinese Taoist master
Qiu Chuji to visit him in Afghanistan, and gave his subjects the right to religious freedom, despite his own shamanistic beliefs.
Death of Genghis Khan and expansion under Ögedei (1227–1241) in 1229 as the successor of Genghis Khan. By
Rashid al-Din, early 14th century. Genghis Khan died on 18 August 1227, by which time the Mongol Empire ruled from the Pacific Ocean to the
Caspian Sea, twice the size of the
Roman Empire or
Umayyad Caliphate at their height, and the largest contiguous state in history. Genghis named his third son, the charismatic
Ögedei, as his heir. According to Mongol tradition, Genghis Khan was
buried in a secret location. The regency was originally held by Ögedei's younger brother
Tolui until Ögedei's formal election at the kurultai in 1229. Among his first actions Ögedei sent troops to subjugate the
Bashkirs,
Bulgars, and other nations in the Kipchak-controlled steppes. In the east, Ögedei's armies re-established Mongol authority in Manchuria, crushing the
Eastern Xia regime and the
Water Tatars. In 1230, the great Khan personally led his army in the campaign against the
Jin dynasty of China. Ögedei's general
Subutai captured the capital of Emperor
Wanyan Shouxu in the
siege of Kaifeng in 1232. The Jin dynasty collapsed in 1234 when the Mongols
captured Caizhou, the town to which Wanyan Shouxu had fled. In 1234, three armies commanded by Ögedei's sons Kochu and Koten and the
Tangut general Chagan invaded southern China. With the assistance of the
Song dynasty, the Mongols finished off the Jin in 1234. In the west, Ögedei's general
Chormaqan destroyed
Jalal al-Din Mangburni, the last
shah of the
Khwarazmian Empire. The small kingdoms in southern Persia voluntarily accepted Mongol supremacy. In East Asia, there were a number of
Mongol campaigns into Goryeo Korea, but Ögedei's attempt to annex the
Korean Peninsula met with little success.
Gojong, the king of
Goryeo, surrendered but later revolted and massacred Mongol
darughachis (overseers); he then moved his imperial court from
Gaeseong to
Ganghwa Island. In 1235, the Mongols established
Karakorum as their capital lasting until 1260. During that period, Ögedei Khan ordered the construction of a palace within the surrounding of its walls.
Invasions of Kievan Rus' and China Meanwhile, in an offensive action against the Song dynasty, Mongol armies captured Siyang-yang, the
Yangtze and
Sichuan, but did not secure their control over the conquered areas. The Song generals were able to recapture Siyang-yang from the Mongols in 1239. After the sudden death of Ögedei's son Kochu in Chinese territory, the Mongols withdrew from southern China, although Kochu's brother Prince Koten invaded
Tibet immediately after their withdrawal. by
Batu Khan in 1238,
miniature from a 16th-century chronicle|alt=Painting of a battle scene
Batu Khan, another grandson of Genghis Khan, overran the territories of the Bulgars,
Alans, Kipchaks, Bashkirs,
Mordvins,
Chuvash, and other nations of the southern Russian steppe. By 1237, the Mongols were encroaching upon
Ryazan, the first Kievan Rus' principality they were to attack. After a three-day siege involving fierce fighting, the Mongols captured the city and massacred its inhabitants. They then proceeded to destroy the army of the
Grand Principality of Vladimir at the
Battle of the Sit River. The Mongols captured the
Alania capital
Maghas in 1238. By 1240, all Kievan Rus'
had fallen to the Asian invaders except for a few northern cities. Mongol troops under Chormaqan in Persia,
connecting his invasion of
Transcaucasia with the invasion of Batu and Subutai, forced the
Georgian and
Armenian nobles to surrender as well. though the invasions into India eventually failed and were forced to retreat. In northeastern Asia, Ögedei agreed to end the conflict with Goryeo by making it a client state and sent Mongol princesses to wed Goryeo princes. He then reinforced his
kheshig with the Koreans through both diplomacy and military force.
Push into Central Europe The
advance into Europe continued with Mongol invasions of Poland and Hungary. When the western flank of the Mongols plundered Polish cities, a European alliance among the
Poles, the
Moravians, and the Christian military orders of the
Hospitallers,
Teutonic Knights, and the
Templars assembled sufficient forces to halt, albeit briefly, the Mongol advance
at Legnica. The
Hungarian army, their
Croatian allies and the Knights Templar were beaten by the Mongols at the banks of the
Sajo River on 11 April 1241. Before Batu's forces could continue on to
Vienna and northern
Albania, news of Ögedei's death in December 1241 brought a halt to the invasion. As was customary in Mongol military tradition, all princes of Genghis's line had to attend the kurultai to elect a successor. Batu and his western Mongol army withdrew from Central Europe the next year. Today researchers doubt that Ögedei's death was the sole reason for the Mongols withdrawal. Batu did not return to Mongolia, so a new khan was not elected until 1246. Climatic and environmental factors, as well as the strong fortifications and castles of Europe, played an important role in the Mongols' decision to withdraw.
Post-Ögedei power struggles (1241–1251) on the throne of the
Golden Horde Following the Great Khan Ögedei's death in 1241, and before the next kurultai, Ögedei's widow
Töregene took over the empire. She persecuted her husband's Khitan and Muslim officials and gave high positions to her own allies. She built palaces, cathedrals, and social structures on an imperial scale, supporting religion and education. She was able to win over most Mongol aristocrats to support Ögedei's son
Güyük. But Batu, ruler of the
Golden Horde, refused to come to the kurultai, claiming that he was ill and that the climate was too harsh for him. The resulting stalemate lasted more than four years and further destabilized the unity of the empire. When Genghis Khan's youngest brother
Temüge threatened to seize the throne, Güyük came to Karakorum to try to secure his position. Batu eventually agreed to send his brothers and generals to the kurultai convened by Töregene in 1246. Güyük by this time was ill and alcoholic, but his campaigns in Manchuria and Europe gave him the kind of stature necessary for a great khan. He was duly elected at a ceremony attended by Mongols and foreign dignitaries from both within and without the empire — leaders of vassal nations, representatives from Rome, and other entities who came to the kurultai to show their respects and conduct diplomacy. demanding
Pope Innocent IV's submission. The 1246 letter was written in Persian. Güyük took steps to reduce corruption, announcing that he would continue the policies of his father Ögedei, not those of Töregene. He punished Töregene's supporters, except for governor
Arghun the Elder. He also replaced young
Qara Hülëgü, the khan of the
Chagatai Khanate, with his favorite cousin
Yesü Möngke, to assert his newly conferred powers. He restored his father's officials to their former positions and was surrounded by Uyghur,
Naiman and Central Asian officials, favoring
Han Chinese commanders who had helped his father conquer Northern China. He continued military operations in Korea, advanced into Song China in the south, and into Iraq in the west, and ordered an empire-wide census. Güyük also divided the Sultanate of Rum between
Izz-ad-Din Kaykawus and
Rukn ad-Din Kilij Arslan, though Kaykawus disagreed with this decision. Not all parts of the empire respected Güyük's election. The
Hashshashins, former Mongol allies whose Grand Master Hasan Jalalud-Din had offered his submission to Genghis Khan in 1221, angered Güyük by refusing to submit. Instead he murdered the Mongol generals in Persia. Güyük appointed his best friend's father
Eljigidei as chief commander of the troops in Persia and gave them the task of both reducing the strongholds of the
Nizari Ismailis and conquering the
Abbasids at the center of the Islamic world, Iran and
Iraq.
Death of Güyük (1248) In 1248, Güyük raised more troops and suddenly marched westward from the Mongol capital of Karakorum. The reasoning was unclear. Some sources wrote that he sought to recuperate at his personal estate, Emyl; others suggested that he might have been moving to join Eljigidei to conduct a full-scale conquest of the Middle East, or possibly to make a surprise attack on his rival cousin Batu Khan in
Kievan Rus. Suspicious of Güyük's motives,
Sorghaghtani Beki, the widow of Genghis's son Tolui, secretly warned her nephew Batu of Güyük's approach. Batu had himself been traveling eastward at the time, possibly to pay homage, or perhaps with other plans in mind. Before the forces of Batu and Güyük met, Güyük, sick and worn out by travel, died en route at Qum-Senggir (Hong-siang-yi-eulh) in
Xinjiang, possibly a victim of poison. |alt=Photograph of a field with a large stone tortoise Güyük's widow
Oghul Qaimish stepped forward to take control of the empire, but she lacked the skills of her mother-in-law Töregene, and her young sons Khoja and Naku and other princes challenged her authority. To decide on a new great khan, Batu called a kurultai on his own territory in 1250. As it was far from the
Mongol heartland, members of the Ögedeid and Chagataid families refused to attend. The kurultai offered the throne to Batu, but he rejected it, claiming he had no interest in the position. Batu instead nominated
Möngke, a grandson of Genghis from his son Tolui's lineage. Möngke was leading a Mongol army in Rus, the northern Caucasus and Hungary. The pro-Tolui faction supported Batu's choice, and Möngke was elected; though given the kurultai's limited attendance and location, it was of questionable validity. Batu sent Möngke, under the protection of his brothers,
Berke and Tukhtemur, and his son
Sartaq to assemble a more formal kurultai at Kodoe Aral in the heartland. The supporters of Möngke repeatedly invited Oghul Qaimish and the other major Ögedeid and Chagataid princes to attend the kurultai, but they refused each time. The Ögedeid and Chagataid princes refused to accept a descendant of Genghis's son Tolui as leader, demanding that only descendants of Genghis's son Ögedei could be great khan.
Rule of Möngke Khan (1251–1259) When Möngke's mother Sorghaghtani and their cousin
Berke organized a second kurultai on 1 July 1251, the assembled throng proclaimed Möngke great khan of the Mongol Empire. This marked a major shift in the leadership of the empire, transferring power from the descendants of Genghis's son Ögedei to the descendants of Genghis's son Tolui. The decision was acknowledged by a few of the Ögedeid and Chagataid princes, such as Möngke's cousin
Kadan and the deposed khan Qara Hülëgü, but one of the other legitimate heirs, Ögedei's grandson Shiremun, sought to topple Möngke. Shiremun moved with his own forces toward the emperor's nomadic palace with a plan for an armed attack, but Möngke was alerted by his falconer of the plan. Möngke ordered an investigation of the plot, which led to a series of major trials all across the empire. Many members of the Mongol elite were found guilty and put to death, with estimates ranging from 77 to 300, though princes of Genghis's royal line were often exiled rather than executed. Möngke confiscated the estates of the Ögedeid and the Chagatai families and shared the western part of the empire with his ally Batu Khan. After the bloody purge, Möngke ordered a general amnesty for prisoners and captives, but thereafter the power of the great khan's throne remained firmly with the descendants of Tolui.
Administrative reforms Möngke was a serious man who followed the laws of his ancestors and avoided alcoholism. He was tolerant of outside religions and artistic styles, leading to the building of foreign merchants' quarters,
Buddhist monasteries,
mosques, and
Christian churches in the Mongol capital. As construction projects continued, Karakorum was adorned with Chinese, European, and
Persian architecture. One famous example was a large silver tree with cleverly designed pipes that dispensed various drinks. The tree, topped by a triumphant angel, was crafted by
Guillaume Boucher, a Parisian goldsmith. , Genghis Khan's grandson and founder of the
Il-Khanate. From a medieval Persian manuscript.|alt=Stylized line drawing of Hulagu, seated and drinking from a bowl Although he had a strong Chinese contingent, Möngke relied heavily on Muslim and Mongol administrators and launched a series of economic reforms to make government expenses more predictable. His court limited government spending and prohibited nobles and troops from abusing civilians or issuing edicts without authorization. He commuted the contribution system to a fixed poll tax which was collected by imperial agents and forwarded to units in need. His court also tried to lighten the
tax burden on commoners by reducing tax rates. He also centralized control of monetary affairs and reinforced the guards at the postal relays. Möngke ordered an empire-wide census in 1252 that took several years to complete and was not finished until
Novgorod in the far northwest was counted in 1258. In another move to consolidate his power, Möngke assigned his brothers
Hulagu and
Kublai to rule Persia and Mongol-held China respectively. In the southern part of the empire he continued his predecessors' struggle against the Song dynasty. In order to outflank the Song from three directions, Möngke dispatched Mongol armies under his brother Kublai to
Yunnan, and under his uncle Iyeku to subdue Korea and pressure the Song from that direction as well. Kublai conquered the
Dali Kingdom in 1253 after the Dali King Duan Xingzhi defected to the Mongols and helped them conquer the rest of
Yunnan. Möngke's general Qoridai stabilized his control over Tibet, inducing leading monasteries to submit to Mongol rule. Subutai's son Uryankhadai reduced the neighboring peoples of Yunnan to submission and went to war with the kingdom of
Đại Việt under the
Trần dynasty in northern Vietnam in 1258, but they had to draw back. The Mongol Empire tried to invade Đại Việt again in 1285 and 1287 but were defeated both times.
New invasions of the Middle East and Southern China After stabilizing the empire's finances, Möngke once again sought to expand its borders. At kurultais in Karakorum in 1253 and 1258 he approved new invasions of the Middle East and
south China. Möngke put Hulagu in overall charge of military and civil affairs in Persia, and appointed Chagataids and Jochids to join Hulagu's army. The Muslims from
Qazvin denounced the menace of the
Nizari Ismailis, a well-known sect of
Shiites. The Mongol Naiman commander
Kitbuqa began to assault several Ismaili fortresses in 1253, before Hulagu advanced in 1256. Ismaili Grand Master
Rukn al-Din Khurshah surrendered in 1257 and was executed. All of the
Ismaili strongholds in Persia were destroyed by Hulagu's army in 1257, except for
Girdkuh which held out until 1271. The center of the Islamic Empire at the time was Baghdad, which had held power for 500 years but was suffering internal divisions. When its caliph
al-Mustasim refused to submit to the Mongols,
Baghdad was besieged and captured by the Mongols in 1258 and subjected to a merciless sack, an event considered one of the most catastrophic events in the history of Islam, and sometimes compared to the
rupture of the Kaaba. With the destruction of the Abbasid Caliphate, Hulagu had an open route to Syria and moved against the other Muslim powers in the region. His army advanced toward
Ayyubid-ruled Syria, capturing small local states en route. The sultan
Al-Nasir Yusuf of the Ayyubids refused to show himself before Hulagu; however, he had accepted Mongol supremacy two decades earlier. When Hulagu headed further west, the
Armenians from
Cilicia, the
Seljuks from
Rum and the Christian realms of
Antioch and
Tripoli submitted to Mongol authority, joining them in their assault against the Muslims. While some cities surrendered without resisting, others, such as Mayafarriqin fought back; their populations were massacred and the cities were sacked.
Death of Möngke Khan (1259) Meanwhile, in the northwestern portion of the empire, Batu's successor and younger brother Berke sent punitive expeditions to
Ukraine,
Belarus,
Lithuania, and
Poland. Dissension began brewing between the northwestern and southwestern sections of the Mongol Empire as Batu suspected that Hulagu's invasion of Western Asia would result in the elimination of Batu's own dominance there. In the southern part of the empire, Möngke Khan himself led his army, but did not complete the conquest of China. Military operations were generally successful, but prolonged, so the forces did not withdraw to the north as was customary when the weather turned hot. Disease ravaged the Mongol forces with bloody epidemics, and Möngke died there on 11 August 1259. This event began a new chapter in the history of the Mongols, as again a decision needed to be made on a new great khan. Mongol armies across the empire withdrew from their campaigns to convene a new kurultai. ==Division of the empire==