During the winter of 1258, the cooler weather in Baghdad provided an opportunity for the Mongol cavalry, unaccustomed to the heat of the Middle East, to station their forces near the gates of this magnificent metropolis, which was at the height of its power. Hulagu Khan, the grandson of Genghis Khan, commanded the Mongol army.

Mongke, the Mongol Khaqan, had earlier written to Al-Mustasim, the Caliph of Baghdad, demanding financial and military support so that the Mongols could overcome a rebel group in Persia. The Mongols knew that conquering Baghdad and Damascus would be necessary to assert their rule over their territories and ensure their access to Mesopotamia. However, prior to such a venture, they had to uproot a group of outlaws in Persia known as the Assassins perched on top of a perilous mountain.

The caliph had refused to provide his own army with basic necessities despite their repeated requests. His wishful thinking that the Mongols would spare Baghdad as the most outstanding center of power in the Middle East had disastrous consequences. The only time he found his army of use was when he decided to utilize their military skills in crushing the resistance of provincial governors who had declined to pay taxes. Those taxes, like all the other income accumulated in the treasury of Baghdad known as the “Beyt-ul-Mal” or the “House of Wealth,” ended up in the palace of Al-Mustasim, where he enjoyed a lavish lifestyle, entertaining his beloved exotic birds.

The presence of a traitor in the court of Al-Mustasim further complicated matters for the kingdom. That traitor was none other than the caliph’s grand vizier, a man by the name of Ibn Alqami. Ibn Alqami enticed the caliph to ignore Mongol demands, a refusal that gave the Mongols the pretext they needed to invade Baghdad.

On the 29th of January 1258, the Mongol cavalry placed Baghdad under siege, and by the 5th of February, the defensive forces were defeated. The caliph dispatched only twenty thousand of his horsemen to confront the Mongols when he could have easily summoned fifty thousand members of the army. Weakened and ill-treated, they were no match for their powerful foes.

After the destruction of Baghdad by the Mongols, Al-Mustasim’s wealth became the instrument of his death. Hulagu ordered that they keep him in a room full of his accumulated gold but give him no food and water. “The Travels of Marco Polo” quotes Hulagu as having said to the caliph, “Eat of thy treasure as much as thou wilt, since thou art so fond of it.” The caliph was then rolled in one of his expensive rugs and was trampled to death.

Although Baghdad’s inhabitants suffered much during the invasion, ultimately, however, the land regained its livelihood under Mongol rule. Among the disastrous consequences of the Mongol attack on Baghdad was the destruction of its great library, known as Darol-Hikmat or “The House of Wisdom,” where countless hand-written books on all subjects from literature to mathematics and astronomy were kept.