The Great Campaigns: Conquest of the Middle East and the Empire's Fragmentation

Key Insight

With the empire's finances stabilized, Mongke Khan summoned a khuriltai in 1253 to plan new conquests, prioritizing campaigns against the Sung dynasty in South China and the Muslim civilizations of the Arab states. He assigned Hulegu, his militarily experienced brother, to lead the Army of the Right to attack Baghdad, Damascus, and Cairo. Khubilai, despite his lack of military experience, was tasked with conquering the Sung dynasty, while Mongke remained in Mongolia and Arik Boke managed the central administration. Hulegu's campaign began with advance troops clearing paths and probing enemy forces, employing a large engineering corps with Chinese and European craftsmen, and a slower, more ostentatious advance compared to Genghis Khan's rapid movements.

Hulegu's first major objective was to conquer the Nizari Ismailis, or Assassins, a heretical Muslim sect fortified in numerous mountain castles from Afghanistan to Syria, with Alamut as their key stronghold. Using a combination of massive military force and offers of clemency, Hulegu captured the Grand Master, paraded him to other castles to secure surrenders, and then executed him and his party by trampling near Karakorum in 1257. With this route cleared, Hulegu marched on Baghdad, the Arab world's wealthiest city and symbolic center, issuing legal grievances and demanding submission. The Caliph defiantly refused, believing the Muslim world would unite to defend him.

In January 1258, Hulegu's armies, including Armenian and Georgian vassals, encircled Baghdad. Leveraging Christian allies within the city through secret envoys, Hulegu promised special treatment for minorities. The Mongols utilized innovative siege tactics, chopping down date palm trees for missiles, using gunpowder weapons (iron-tubed devices firing shrapnel, proto-grenades, mortars, incendiary rockets), and diverting the Tigris River to flood enemy camps. Baghdad's walls were breached on February 5, 1258, leading to the Caliph's capitulation after five days. The city was looted for 17 days, churches were protected, and one palace was gifted to the Christian Catholikos Makikha. The Caliph and his male heirs were executed without bloodshed, wrapped in carpets or sacks and kicked/trampled to death. The Mongols reached the Mediterranean for the second time, but their western expansion ended on September 3, 1260, when Mamluk forces defeated a Mongol detachment at Ayn al-Jalut in modern-day Israel.