In 1253, Mongke Khan, Great Khan of the Mongol Empire (he was the eldest son of Genghis Khan’s son Tolui and Sorghaghtani Beki), decided that it was time to achieve Genghis Khan’s dream of conquering the Islamic civilization in the Levant and the Sung dynasty’s territory in South China. He summoned his two brothers, Hulagu and Kublai. He assigned the Arab lands to Hulagu, who was known for his military expertise, and to Kublai, known for his good knowledge of Chinese culture, he assigned South China. Being the Great Khan, Mongke would remain in the center of Mongolia.
In this article I will talk about Hulagu’s campaign against the Nizari Ismailis sect. Hulagu collected the largest army ever assembled by the Mongols. His first target was to conquer Baghdad, and after that he planned to capture Damascus and Cairo. But to reach Baghdad, his military would have to pass through areas which were in the control of the Nizari Ismailis sect whose members were known in Western Europe as the Assassins. In Mongolia, this sect was known as the Hashshashin—it was rumored that their assassins operated under the influence of hashish. The leader of the sect was the Imam, also known as the Grand Master and the Old Man of the Mountain.
In the time of Genghis Khan’s invasion of the Levant, the Imam had sided with the Mongols. When Genghis Khan’s military returned to Mongolia after destroying the Turkic sultan of the Khwarezmian Empire in Iran, there was a power vacuum which the Nizari Ismailis sect had occupied. In the time of Hulagu, the sect was in control of territory extending from Afghanistan to Syria. They operated out of a string of self-sufficient and strategic castles located on mountainsides. The most important of these castles was Alamut, the Eagle’s Nest, in northern Persia. They did not possess a conventional military, but they exercised tremendous political power because of the fearsome reputation of their assassins and their brutal terror tactics.
The Nizari Ismailis sect had tried to assassinate the Great Khan Mongke after he ascended the throne of the Mongol Empire in 1251. Claiming that they wanted to pay homage to the new Great Khan, the sect had sent a large delegation, which included forty assassins, to Mongolia. But the Mongols did not allow the delegation to approach their Great Khan. They were turned back and the assassination attempt was thwarted. William of Rubruck, a Flemish priest sent on a mission to Mongolia in 1253, was surprised to see the immense security precautions around the Great Khan. The security was in response to the assassination attempts by the Nizari Ismaili sect.
Mongke and Hulagu were determined to crush the sect of assassins. When Hulagu reached the assassin territory in March 1253, the Imam of Nizari Ismaili sect had been killed in factional fighting and the power had gone into the hands of his son, who was in his late twenties and was rumored to be a hashish addict. The Mongols started destroying the strategic castles through which the Nizari Ismaili sect exercised its power. After he had lost several of his castles in the outlying areas, the new Imam tried to appease the Mongols. He started sending conciliatory messages to the Mongol Camp. Hulagu would consider nothing less than absolute capitulation. But he agreed to show clemency to the Imam if he surrendered.
In 1256, the Mongols were fighting in the Nizari Ismaili heartland of Alamut and Rudbar. Hulegu had brought with him a core of engineers for building armored siege towers, bridges, and catapults. To destroy the fortifications in the mountainside castles, his army used armored siege towers to hurl javelins dipped in burning pitch. They used an advanced form of gunpowder to blow the walls of the castles. Once the fortifications were destroyed, and gaps had been created in the castle walls, the Mongol warriors would scale the steep mountains and kill everyone inside the castles in hand to hand fighting.
In November 1256, the Imam of Nizari Ismailis realized that his sect could not fight Hulegu’s Mongol army. He decided to surrender unconditionally. He ordered his castles to capitulate to the Mongols and dismantle their fortifications. After taking control of the Imam, Hulagu paraded him before the Nizari Ismaili castles that were still holding out and forced them to surrender.
By the spring of 1257, Hulagu was in possession of Nizari Ismaili sect’s entire territory. He had no further use of the Imam, who was dispatched to Mongolia for an audience with the Great Khan Mongke. After a journey of several months, the Imam and his retinue, escorted by Mongol troops, arrived in Mongolia. Here the Imam was berated by Mongke for standing in the way of the Mongol military. He ordered the Imam to return to his homeland. On his way back, the Imam and his retinue were slaughtered by the Mongol troops. Mongke ordered a massacre of the members of the Nizari Ismailis sect. Most estimates suggest that around 100000 followers of the sect were killed.
With the Nizari Ismailis sect vanquished, Hulagu’s road to Baghdad was wide open. He began his march to Baghdad in November 1257. The Mongol military besieged Baghdad on January 29, 1258, and in just thirteen days, the city capitulated. The Mongol army marched into the city on February 10, 1258. The Western crusaders could not conquer Baghdad in two centuries, but the Mongol army conquered the city in thirteen days.