Many people embraced Islam at his hand.

He then visited Bakhrank, the site of Imam al-Bukhārī’s grave. He rebuilt its dome, hung curtains and lamps upon it, and when the people of Samarqand asked him to stay with them he remained a few days before returning to Bukhārā. An amir accepted Islam through him and became the shaykh’s doorkeeper, so the shaykh named him Muʾmin.

Among the Tatars the shaykh was called Ulugh Shaykh—“the Great Shaykh”—and this was the name by which Hülegü knew him. From Saqsīn, Berke (1) ibn Tūshī ibn Chinggis Khān sent a messenger to the shaykh to receive from him the pledge of Islam.

Berke’s brother Bātū was an oppressive unbeliever who had seized the territories of Saqsīn, Bulghār, the Saqlab, and the Qifjāq as far as Darband. Berke had yet a younger brother known as Berke Har. Bātū, despite his unbelief, was fond of the shaykh; when he learned that his brother Berke Khān had become the shaykh’s disciple he rejoiced and asked permission to visit the shaykh. Leave was granted, so he set out from Bulghār to Jand, then to Otrar, and finally reached Bukhārā. He arrived after the night prayer, in deep snow, and did not seek admission until daybreak. A trustworthy informant told me that Berke Khān stood at the door the whole night, praying intermittently, until morning. Then he entered, kissed the shaykh’s foot, and performed the two-cycle prayer in greeting of the place. The shaykh was pleased with this. A number of his amirs embraced Islam; the shaykh accepted their pledge, wrote out litanies and supplications for them, and ordered Berke to return. His soul, however, was uneasy, whereupon the shaykh said, “You have come to us with a large retinue, and I do not wish to command them to disperse; I would rather you remain within your own sovereignty.”

Berke had sixty (2) wives; the shaykh instructed him to keep four and divorce the rest, and he complied. He returned home, openly raised the banners of the religion, and many people embraced Islam with him. They began learning the obligatory acts, and scholars travelled to join him. Later wars broke out between him and his cousin Hülegü. Berke Khān died in Rabīʿ al-Ākhir, 665 AH, and his charitable gifts continued to reach the majority of scholars.