Shajarat al-Durrr was an Egyptian Sultana whose reign saw the end of the Ayyubid and beginning of the Mamluk Dynasty. She began her life at court as a Turkish slave and favorite concubine of Ayyubid Sultan, al-Salih Najm al-Din Ayyub before he became a sultan. In 1239-40/ 637 AH, when she bore him a son named Khalil, he manumitted and married her.1 Although the son died after a few months, her identity as mother of Khalil, i.e. Umm Khalil or Walidat al-Khalil, became important for her authority, given the absence of al-Salih's living sons in later years. She was de facto ruler in al-Salih's absence when he would leave for expeditions.

She was made the sultana by the Mamluks after the death of Sultan Salih and eventual killing of his heir in 1250/ 648 AH, and her name was the one read in the Friday sermons.2 ʿIzz al-Dīn Aybak al-Turkumānī (d. 1257/ 655 AH) was made his commander who later married her.3 While she performed many of the tasks of a sultan from the harem, others were not carried out directly by her, such as leading the army or having public processions.4 It is believed that she had a hand in getting Aybak assassinated after he started challenging her authority and after a few days of that, she herself was assassinated in 1257/ 655 AH.5

Shajarat al-Durr was an important agent amongst the dramatic events that brought the eventual close of the Ayyubid dynasty and ushering in the rule of Mamluks.6 As the most powerful woman in Egypt and with no direct heir, she reflected her patronage by commissioning a tomb for her husband and also one for herself. 

Notes 

1. Ammann, EI2. 
2. Ruggles, “Visible and Invisible Bodies”, 65. 
3. Ammann, EI2. 
4. Ruggles, “Visible and Invisible Bodies”, 65. 
5. Ammann, EI2.
6. Ruggles, “Visible and Invisible Bodies”, 65. 

Sources 

Ammann, L. ‘’S̲h̲ad̲j̲ar Al-Durr'’. In Encyclopaedia of Islam, Second Edition. Edited by P. Bearman, Th. Bianquis, C.E. Bosworth, E. van Donzel, W.P. Heinrichs, P.J. Bearman. <http://dx.doi.org/10.1163/1573-3912_islam_SIM_6738> 

Ruggles, D. Fairchild. "Visible and Invisible Bodies: The Architectural Patronage of Shajar al-Durr." Muqarnas: An Annual On The Visual Cultures Of The Islamic World 32 (2015): 63-78.