The expansion of Mongol power across Western Asia depended upon the conquest of the Islamic lands, the complete seizure of which would be impossible without dismantling the ardent Nizari Ismaili state.
Consisting of over fifty strongholds unified under the central power of the Imam, the Nizaris represented a significant obstruction to the Mongol undertaking.
The task of successively destroying these castles was assigned to Hulegu, under the direction of his brother, the Great Khan Möngke.
Only after their destruction could the invading Mongols proceed to remove the Abbasid caliph from Baghdad and advance their conquest westward.

Before Hulegu set forth toward Persia, the threat to the Muslim world posed by the swelling Mongol force was perceived by the Ismaili Imam ‘Ala al-Din Muhammad, who in 1238 joined the Abbasid caliph, al-Mustansir, in appealing to the European monarchs of England and France to coalesce in a Christian-Muslim Alliance against the Mongols.
Although the European rulers did not accept this proposal, the Ismaili Imam partnered again with the Sunni caliph in 1246 AD when the two journeyed to the enthronement of the Great Khan Güyük in Mongolia.
Their joint expressions of peace were not acknowledged by the Mongol lord and shortly after in 1252 AD, the Mongols arrived in Quhistan.

The first Mongol attack on the Ismailis came in April 1253 AD, when many of the Quhistani fortresses were lost to the Christian Mongol general Ket-Buqa.
By May, the Mongol troops had proceeded to the fortress of Girdkuh where Ismaili forces held ground for several months.
In December, a cholera outbreak within the castle weakened the Ismaili defences.
Reinforcements quickly arrived from the neighbouring Alamut fortress and thwarted the attacking Mongols, killing several hundred of Ket-Buqa's troops.
The castle was saved but the subsequent Mongol assaults on the towns of Tun and Tus resulted in massacres.
Across Khurasan the Mongols imposed tyrannical laws and were responsible for the mass displacement of the province's population.

After the massacres at Tun in 1256 AD, Hulegu became directly involved in the Mongol campaign to eliminate the Ismaili centres of power.
From a lavish tent erected for him at Tus, Hulegu summoned the Ismaili governor at Quhistan, Nasir al-Din Muhtasham and demanded the surrender of all fortresses in his province.
Nasir al-Din explained that submission could only come at the Imam's orders and that he, as governor, was powerless to seek the Ismailis' compliance.

Meanwhile, Imam ‘Ala al-Din Mohammad, who had been murdered, was succeeded by his son Rukn al-Din in 1255 AD.
In 1256 AD, Rukn al-Din commenced a series of gestures demonstrating his submission to the Mongols.
In a show of his compliance and at the demand of Hulegu, Rukn al-Din began the dismantling process at Alamut, Maymundiz and Lamasar, removing towers and battlements.
However, as winter approached, Hulegu took these gestures to be a means of delaying his seizure of the castles and on November 8, 1256, the Mongol troops quickly encircled the Maymundiz fortress and residence of the Imam.
After four days of preliminary bombardment with significant casualties for both sides, the Mongols assembled their mangonels around the castle in preparation for a direct siege.
There was still no snow on the ground and the attacks proceeded, forcing Rukn al-Din to declare his surrender in exchange for his and his family's safe passage.
A yarligh (decree) was drafted and taken to the Imam by Juwayni.
After another bombardment, Rukn al-Din descended from Maymundiz on 19 November.

In the hands of Hulegu, Rukn al-Din was forced to send the message of surrender to all the castles in the Alamut valley.
At the Alamut fortress, the Mongol Prince Balaghai led his troops to the base of the castle, calling for the surrender of the commander of Alamut, Muqaddam al-Din.
It was decreed that should he surrender and pledge his allegiance to the Great Khan within one day, the lives of those at Alamut would be spared.
Maymundiz was reluctant and wondered if the Imam's message o
The expansion of Mongol power across Western Asia depended upon the conquest of the Islamic lands, the complete seizure of which would be impossible without dismantling the ardent Nizari Ismaili state. Consisting of over fifty strongholds unified under the central power of the Imam, the Nizaris represented a significant obstruction to the Mongol undertaking. The task of successively destroying these castles was assigned to Hulegu, under the direction of his brother, the Great Khan Möngke. Only after their destruction could the invading Mongols proceed to remove the Abbasid caliph from Baghdad and advance their conquest westward.
Before Hulegu set forth toward Persia, the threat to the Muslim world posed by the swelling Mongol force was perceived by the Ismaili Imam ‘Ala al-Din Muhammad, who in 1238 joined the Abbasid caliph, al-Mustansir, in appealing to the European monarchs of England and France to coalesce in a Christian-Muslim Alliance against the Mongols. Although the European rulers did not accept this proposal, the Ismaili Imam partnered again with the Sunni caliph in 1246 AD when the two journeyed to the enthronement of the Great Khan Güyük in Mongolia. Their joint expressions of peace were not acknowledged by the Mongol lord and shortly after in 1252 AD, the Mongols arrived in Quhistan.
The first Mongol attack on the Ismailis came in April 1253 AD, when many of the Quhistani fortresses were lost to the Christian Mongol general Ket-Buqa. By May, the Mongol troops had proceeded to the fortress of Girdkuh where Ismaili forces held ground for several months. In December, a cholera outbreak within the castle weakened the Ismaili defences. Reinforcements quickly arrived from the neighbouring Alamut fortress and thwarted the attacking Mongols, killing several hundred of Ket-Buqa's troops. The castle was saved but the subsequent Mongol assaults on the towns of Tun and Tus resulted in massacres. Across Khurasan the Mongols imposed tyrannical laws and were responsible for the mass displacement of the province's population.
After the massacres at Tun in 1256 AD, Hulegu became directly involved in the Mongol campaign to eliminate the Ismaili centres of power. From a lavish tent erected for him at Tus, Hulegu summoned the Ismaili governor at Quhistan, Nasir al-Din Muhtasham and demanded the surrender of all fortresses in his province. Nasir al-Din explained that submission could only come at the Imam's orders and that he, as governor, was powerless to seek the Ismailis' compliance.
Meanwhile, Imam ‘Ala al-Din Mohammad, who had been murdered, was succeeded by his son Rukn al-Din in 1255 AD. In 1256 AD, Rukn al-Din commenced a series of gestures demonstrating his submission to the Mongols. In a show of his compliance and at the demand of Hulegu, Rukn al-Din began the dismantling process at Alamut, Maymundiz and Lamasar, removing towers and battlements. However, as winter approached, Hulegu took these gestures to be a means of delaying his seizure of the castles and on November 8, 1256, the Mongol troops quickly encircled the Maymundiz fortress and residence of the Imam. After four days of preliminary bombardment with significant casualties for both sides, the Mongols assembled their mangonels around the castle in preparation for a direct siege. There was still no snow on the ground and the attacks proceeded, forcing Rukn al-Din to declare his surrender in exchange for his and his family's safe passage. A yarligh (decree) was drafted and taken to the Imam by Juwayni. After another bombardment, Rukn al-Din descended from Maymundiz on 19 November.
In the hands of Hulegu, Rukn al-Din was forced to send the message of surrender to all the castles in the Alamut valley. At the Alamut fortress, the Mongol Prince Balaghai led his troops to the base of the castle, calling for the surrender of the commander of Alamut, Muqaddam al-Din. It was decreed that should he surrender and pledge his allegiance to the Great Khan within one day, the lives of those at Alamut would be spared. Maymundiz was reluctant and wondered if the Imam's message o
Alamut Castle