Möngke Khan (also Möngke Khagan or Möngke; 11 January 1209 – 11 August 1259) was the fourth khagan of the Mongol Empire, ruling from 1 July 1251 to 11 August 1259. He was the first Khagan from the Toluid line, and made significant reforms to improve the administration of the Empire during his reign. Under Möngke, the Mongols conquered Iraq and Syria as well as the Dali Kingdom (modern Yunnan).
Möngke's death in 1259 without a designated successor led to the four-year Toluid Civil War between his two younger brothers, Kublai Khan and Ariq Böke. Though Kublai Khan eventually won, the succession war and the subsequent Kaidu–Kublai war essentially resulted in the permanent division of the Mongol Empire.
Möngke was born on 11 January 1209, as the eldest son of Genghis Khan's teenaged son Tolui and Sorghaghtani Beki. Teb Tengri Khokhcuu, a shaman, claimed to have seen in the stars a great future for the child and bestowed on him the name Möngke, meaning 'eternal' in Mongolian. His uncle Ögedei Khan's childless queen Angqui raised him at her orda (nomadic palace). Ögedei instructed Persian scholar Idi-dan Muhammed to teach writing to Möngke.
On his way back home after the Mongol conquest of the Khwarazmian Empire, Genghis Khan performed a ceremony on his grandsons Möngke and Kublai after their first hunting in 1224 near the Ili River. Möngke was fifteen years old, and with his brother, Kublai, killed a rabbit and an antelope. Their grandfather smeared fat from the killed animals onto their middle fingers following the Mongol tradition.
In 1230, Möngke went to war for the first time, following Ögedei and his father Tolui into battle against the Jin dynasty. Tolui died in 1232, and Ögedei appointed Sorghaghtani head of the Toluid appanage. Following the Mongol custom, Möngke inherited at least one of his father's wives, Oghul-Khoimish of the Oirat clan. Möngke deeply loved her and gave special favor to her elder daughter, Shirin.
Ögedei dispatched him along with his relatives to attack the Kipchaks, Kievan Rus', and Bulgars in the west in 1235. When the most formidable Kipchak chief, Bachman, fled to an island in the Volga delta Möngke crossed the river and captured him. When he ordered Bachman to bend down on his knees, Bachman refused and was executed by Möngke's brother Bujek. Möngke also engaged in hand-to-hand combat during the Mongol invasion of Rus'. While his cousins, Shiban and Büri, went to Crimea, Möngke and Kadan, a son of Ögedei, were ordered to reduce the tribes in the Caucasus. The Mongols captured the Alan capital Maghas and massacred its inhabitants. Many chiefs of the Alans and Circassians surrendered to Möngke. After the invasion of Eastern Europe, Möngke would bring them back to Mongolia. He also participated in the Siege of Kiev (1240). Möngke was apparently taken by the splendour of Kiev and offered the city surrender, but his envoys were killed. After Batu's army joined Möngke's, they sacked the city. He also fought alongside Batu at the Battle of Mohi. In the summer of 1241, before the premature end of the campaign. Möngke returned home after his uncle Ögedei recalled him in the winter of 1240–41. However, Ögedei died in December 1241.
In 1246, Temüge, Genghis Khan's sole remaining brother, unsuccessfully tried to seize the throne without confirmation by a kurultai. The new Khagan Güyük entrusted the delicate task of trying the Odchigin ('keeper of the hearth' – a title given to both of Genghis' younger brothers) to Möngke and Orda Khan, the eldest brother of Batu. Güyük eventually died en route to the west in 1248 and Batu and Möngke emerged as the main contenders.
Following his mother Sorghaghtani's advice, Möngke went to the Golden Horde to meet Batu, who was afflicted with gout. Batu decided to support his election and called a kurultai at Ala Qamaq. The leader of the families of Genghis Khan's brothers, and several important generals, came to the kurultai. Güyük's sons Naqu and Khoja attended briefly but then left. Despite vehement objections from Bala, Oghul Qaimish's scribe, the kurultai approved Möngke. Given its limited attendance and location, this kurultai was of questionable validity. Batu sent Möngke under the protection of his brothers, Berke and Tuqa-temur, and his son Sartaq to assemble a formal kurultai at Kodoe Aral in Mongolia. When Sorghaghtani and Berke organized a second kurultai on 1 July 1251, the assembled throng proclaimed Möngke the Great Khan of the Mongol Empire, and a few of the Ögedeid and Chagatayid princes, such as his cousin Kadan and the deposed khan Qara Hülegü, acknowledged the decision.
Shortly thereafter, Oghul's son Khoja and Ögedei's favorite grandson Shiremun came to "pay homage" to Möngke as the new ruler, but they brought the entire army of the Ögedei faction with them. Möngke's Kankali falconer, Kheshig, discovered the preparations for the attack and told his lord. At the end of the investigation under his father's loyal servant Menggesar noyan, he found his relatives guilty but at first wanted to give them mercy as written in the Great Yassa. Möngke's officials opposed it and then he began to punish his relatives. The trials took place in all parts of the empire from Mongolia and China in the east to Afghanistan and Iraq in the west. Möngke and Batu's brother Berke therefore arranged to have Oghul accused of using black magic against Möngke. After she was arrested and questioned by Sorghaghtani, Oghul Qaimish was sewn up into a sack and tossed into a river and drowned, the traditional Mongol punishment for using black magic. Estimates of the deaths of aristocrats, officials, and Mongol commanders include Eljigidei, Yesü Möngke, Büri, and Shiremun and range from 77 to 300. However, most of the princes descended from Genghis Khan who were involved in the plot were given some form of exile. The anti-Möngke plot of a Uyghur scribe, Bala, and the Idiqut Salindi (the monarch of the Uyghurs) was discovered and they were publicly executed. After his accession to the throne in 1251, Möngke announced that he would follow his ancestors but would not imitate the ways of other countries. To increase his legitimacy, in 1252 he retroactively awarded his father the title of Ikh Khagan. Möngke shared the western part of the empire with his ally Batu Khan, ensuring the unity of the empire. Möngke's mother Sorghaghtani died in 1252.
After the defeat of the Ögedeid and Chagataid families, Möngke eliminated their estates and assigned acquiescent family members new territories either in Turkestan or in northwestern China. After the bloody purge, Möngke ordered a general amnesty for prisoners and captives. In another move to consolidate his power, Möngke gave his brothers Kublai and Hulagu supervisory powers in North China and Iran. Rumours spread that his brother Kublai founded a de facto independent ulus (district), and perhaps took for himself some of the tax receipts that should by rights be coming to Karakorum. In 1257 the Emperor sent two tax inspectors to audit Kublai's official. They found fault, listed 142 breaches of regulations, accused Chinese officials, and even had some executed; Kublai's office was abolished. Möngke's authority took over the collection of all taxes in Kublai's estates. As his Confucian and Buddhist advisers pointed out, Kublai first sent his wives to the court of Khagan and then appealed to Möngke in person. They embraced in tears and Möngke forgave his brother.
Möngke drafted his own decrees and kept close watch on their revision. Möngke forbade practices of extravagant costs of the Borjigin and non-Borjigid nobles. He also limited gifts to the princes, converting them into regular salaries, and made the merchants subject to taxes. Möngke limited notorious abuses and sent imperial investigators to supervise the business of the merchants who were sponsored by the Mongols. He prohibited them from using the imperial relay stations, yam (route), and paizas, tablets that gave the bearer authority to demand goods and services from civilian populations. With Güyük dead, many local officials no longer wanted to pay off the paper drafts used by Güyük. Möngke recognized that if he did not meet the financial obligations of Güyük, it would make merchants reluctant to continue business with the Mongols. Möngke paid out all drafts drawn by high ranking Mongol elites to these merchants. Ata-Malik Juvayni stated, "And from what book of history has it been read or heard...that a king paid the debt of another king?" The generals and princes (including his son) who allowed their troops to plunder civilians without authorization were repeatedly punished by Möngke Khan. He used North Chinese, Muslim, and Uyghur officials. The Khagan's chief judge (darughachi) was the Jait-Jalayir official Menggeser, while the chief scribe was the Bulghai of the Keraites, who was a Christian. Nine of the 16 chief provincial officials of Möngke Khan were certainly Muslims. He reappointed Güyük's three officials: Mahmud Yalavach in China, Masud Beg in Turkestan, and Arghun Aqa of the Oirat in Iran. Möngke separated the position of the great judge at court from that of chief scribe.