That was the period of the relative quietness following the death of Genghis Khan.
Where were the Muslims during that period?

They were in their usual dispute, schism, hypocrisy and bad morals. The Muslims did not make use of the calamity that befell the Tatars because of the death of their great leader Genghis Khan, in order to gather themselves and liberate their territories. But, they rather engaged in fighting with each other, and wronging each other.
The disputes between Jalaal Ad-Deen and his brother Ghayyaath Ad-Deen renewed once again and were aggravated, to the extent that the latter cooperated with the enemies of the former in his wars.

Moreover, the entire region was surging with troubles and afflictions, extending beyond Iraq and Persia to all Muslim territories. The wars between the Muslim governors of Shaam and Egypt were continuous, and they never were united, even though they belonged to the same Ayyubid Family, and in some cases, they were full brothers. As a result, a horrible incident took place in 626 A.H.; Bayt Al-Maqdis, previously liberated by Saladin, was handed over to the Crusaders under a peace treaty, according to which the Muslims of Shaam agreed upon giving Bayt Al-Maqdis to the Crusaders, who would, in return, leave some Emirates in Shaam to the Muslims. We seek refuge with Allaah The Almighty from (being sent back to) weakness after power, from (being put to) humiliation after honor, and from (being given to) disappointment after victory.

On the other hand, Jalaal Ad-Deen went on his atrocious wars in the region. He besieged the city of Khalat once again following its rebellion against him. The siege was so much long that its inhabitants were forced to eat the flesh of donkeys and horses, then to eat dogs and cats, and even rats. After that, the city fell in the hand of Jalaal Ad-Deen, who ruined it and killed a great multitude of its men and captured lots of its women, and further enslaved its children and sold them. This crime was unprecedented, as stated by Ibn Al-Atheer, May Allaah Have mercy upon him. Assuredly, Allaah The Almighty Was not to Give him more respite.

However, such events in the Muslim territories interpret why the Tatars committed all their crimes in them, in spite of their vastness, great populations and treasures. Assuredly, this is a norm that is well-established in the universe. The tyrants of the earth should be given power over anyone in such conditions. . Allaah The Almighty aids only the one who helps Him: {If Allaah Should Aid you, no one can overcome you; but if He Should Forsake you, who is there that can aid you after Him?} [Quran 3:160]

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