The last Caliph of Baghdad ascended to his throne in 1242. The position had been powerless for a long time during the Turkish migrations, ruling in name while the cities were virtually independent, but then a series of energetic Caliphs had begun to assert military might in the region. Caliph al-Mutasim allied with the Nizaris before their fall; he had traveled to Güyük Khan’s crowning and tried to ally with both Mongols and Christians against each other, but neither attempt worked. Al-Mutasim is also remembered for his consternation when, during Egypt’s Mamluk Revolution, the widow Shajar el-Durr became Sultan. He is remembered for asking, “Has Egypt run out of men? We can send them some.”
Hulegu Khan had checked off two of his major tasks by 1257: the Lur people of western Iran were easily conquered, and Alamut had surrendered more easily than expected. West of Baghdad, several of the cities had proactively surrendered, so the Ilkhan’s army already had units from Georgia, Armenia, Antioch, Aleppo, and Mosul. Hulegu sent a Mongol embassy to Baghdad demanding submission and tribute. In one of history’s great acts of folly, Caliph al-Mutasim refused.
The Caliph was following his vizier’s advice. The vizier said that the Mongol army was smaller than it really was and assured him of assistance from other Muslim rulers which, in fact, they could not send. They may have been obligated by old treaties, but the realities had changed. Egypt’s Mamluk government might have helped, but they were not willing to extend themselves for a man who had mocked them. Was the vizier’s bad advice intentional treason or incompetence? Judging the past by the present, incompetence and rigidity of thought seem most likely. We’re always fighting the last war, just like Foolish Hans.
The siege began at the start of 1258. Baghdad was ill-prepared. The Caliph believed he had 50,000 fighting men at his disposal, but it turned out to be only 20,000 and not as disciplined or armed as he had thought. After the Mongols were camped on both sides of the Tigris River (a bad sign), the Caliph ordered a sortie to break up the encampment before it could harden into a siege. This went badly.
Moreover, the Mongols had learned a lot about cities by now. First lesson was to delegate strategy and engineering to those with long urban experience. Hulegu’s artillery was commanded by a Han Chinese who came from a many-generational military family. General Guo Kan had sappers attacking the river’s dike system; they opened a flood of river water, cutting off the city’s cavalry retreat. The Caliph and then some leading citizens,began begging to surrender, but Mongols did not reward those who asked too late.
Guo Kan supervised the formal siege of the city. They dug ditches and built a palisade, as had become Mongol practice. Chinese siege engines rolled up behind the palisade and began the bombardment. It took only about ten days for the city to be fully in Mongol hands. Then the city was systematically destroyed.
Effectively all of Baghdad’s population was put to the sword. Nobody is sure how many that was; a low estimate is about 100,000, since the city was not at his peak by 1258. They say Hulegu moved his camp upwind so they wouldn’t have to smell the decaying bodies. But one small sector of the population was apparently spared, the community of Nestorian Christians. Hulegu had a Christian wife, Dokuz Khatun (“Princess Nine”), traveling with him, and she personally interceded.
The Caliph was executed in the way that the Mongols believed proper for royal blood: rolled into a carpet and trampled by horses. This way, no blood reached the Earth to offend it. (Marco Polo heard a different story years later: that the Caliph was locked into a treasure room to starve on the gold he had refused to spend for his city’s defense.) One of his sons went to Karakorum as a hostage, while the others were executed.
The city was carefully looted; it yielded riches like those found in Genghis Khan’s time. When it was empty, historic buildings were burnt and torn down. The city walls and towers were dismantled, the irrigation canals blocked and filled. The loss that really kills the modern heart was the way the Mongols treated the library. The unoffending books were carted out and dumped in the Tigris River, which was already choking with blood and corpses. They say the water turned black as the ink dissolved in a million ancient manuscripts.
What’s surprising about this decision is that Hulegu and his brothers had been educated by a Persian scholar. They were literate and they also spoke at least two or three languages. Their grandfather had set an example of taking scholars back to Karakorum, rather than killing them. Perhaps Hulegu disdained the history of other nations, valuing only the oral histories told by Mongol singers. To us, the Baghdad collection of books was equally valuable as the Alexandrian library. (People often assume that early Muslim invaders burnt the library, but it may have just burned down in the ordinary way.) Alexandria probably had original copies of Aristotle’s books, Greek plays and poems now utterly lost, and irreplaceable Egyptian historical records. Baghdad had books in Sanskrit and perhaps other Indian languages, brought back by the first Muslim conquerors. What price could we put on the original manuscripts for the invention of digit-based mathematics?
When the city was utterly leveled, Hulegu ordered it to be rebuilt. He wanted a trading town in that place, he just didn’t want it to be the fabled Round City, capital of Islam. Symbolically, the Caliphate of Islam was dead and would never rise.
Hulegu had fulfilled the mandate laid on him by Möngke Khan and now the attention of Karakorum would turn to pushing the boundaries of their Chinese empire farther, under Kublai. But there was one glaring problem that Möngke had not foreseen. Their cousin Berke, Batu’s brother, began to rule in Sarai, Russia in 1257 after Batu died. The sons of Tolui (Möngke, Hulegu, Ariq Boke, Kublai) had always gotten along well with the sons of Jochi (Batu, Berke, Orda). But Berke had become a Muslim.
Batu’s Golden Horde had built Sarai in Russia and another Sarai, “Little Sarai,” eastward in Kazakhstan. Before Batu’s death, Berke was the ruler in Little Sarai, where most of the trade traffic was among Muslim cities like Bokhara and Samarkand. As he conversed with Muslim traders, he had experienced a sincere conversion.
This change of heart in Berke was so strong that it threatened his Mongolian identity. The generation he belonged to had a split identity between Nestorian Christianity and Buddhism. Möngke formally became a Buddhist before his death, but always encouraged pluralism of faith as his grandfather had done. Berke was the first prominent Mongolian convert to Islam, and you might think that he’d continue to be pluralistic since it was such a big part of his culture. You’d be wrong. In later Mongol conversions, too, putting on Islam meant putting off tolerance and pluralism.
Berke, now Khan at the main Russian Sarai, was as outraged as any imam at the destruction of his new faith’s holy city. He never forgave Möngke and Hulegu, and he swore revenge. He intended to declare his Golden Horde for Islam and join Mamluk Egypt against his cousins. However, Möngke Khan’s power was too strong at this time for him to take action. Berke brooded and waited.