Founder of the Qadiriyya Sufi order and one of the most renowned saints of the Islamic world. Born in Gilan in 470/1077, he died in Baghdad in 561/1166; his tomb in the Gaylani Mosque complex at Bab al-Sheikh (Rusafa) is a major pilgrimage center. (Sources: TDV 'Abdülkādir-i Geylânî'; Wikidata Q12186500.)