, S̲h̲ayk̲h̲ , the 5th Ṣafawid s̲h̲ayk̲h̲ in line of descent from S̲h̲ayk̲h̲ Ṣafī al-Dīn Isḥāḳ, the founder of the Ṣafawid ṭarīḳa . The son of D̲j̲unayd [q.v.] and K̲h̲adīd̲j̲a Begum, the sister of the Aḳ Ḳoyunlu ruler Uzun Ḥasan, Ḥaydar succeeded his father as head of the Ṣafawid ṭarīḳa at Ardabīl in 864/1460.

Ḥaydar, by his marriage to Ḥalīma Begī Āg̲h̲ā (or Marta; better known as ʿAlams̲h̲āh Begum), the daughter of Uzun Ḥasan and Despina K̲h̲ātūn, the latter the daughter of Calo Johannes, the Emperor of Trebizond, maintained the close alliance w…