2 May 1250–July 1250 AD: Shajar al-Durr (شجر الدر, "Tree of Pearls") whose Royal Name was al-Malika `Aṣmat ad-Dīn Umm-Khalīl Shajar ad-Durr (الملكة عصمة الدين أم خليل شجر الدر) (nicknamed: أم خليل, Umm Khalil; mother of Khalil) (died 28 April 1257 in Cairo). She was the wife of Sultan al-Malik As-Salih Ayyub (الملك الصالح نجم الدين ايوب), Egypt's seventh Ayyubid Sultan and later married Izz al-Din Aybak, Egypt's Sultan of the Bahri Mamluk dynasty. Aybak married her to claim access to the throne. Shajar al-Durr played a crucial role after the death of her first husband in Al-Mansura (22 November 1249) during the Seventh Crusade (1249–1250). She became the Sultana of Egypt on May 2, 1250 (648 AH), marking the end of the Ayyubid reign and the start of the Mamluk era. Her reign was short, lasting under three months. Many Muslim historians believed that she was of Turkic origin and some believed that she was of Armenian origin