The notice of Abū Bakr Ya'īsh b. Muḥammad b. Ya'īsh in Ibn Bashkuwāl, ed. Codera, p. 628, gives his death as in 418 or 419. This confirms the view that Dhunnunid rule began before 423. Abū Bakr Ya'īsh must have reached power about 400: Ibn Kauthar was killed by his orders in 403 (loc. cit., p. 39) while at the funeral of a certain Qushairī (not the mystic) in 400 Ibn Ya'īsh, presumably Muḥammad the father, took the prayers.