Shaykh al-Islām

[2]: 399  In the central and western lands of Islam, it was an informal title given to jurists whose fatwas were particularly influential, while in the east it came to be conferred by rulers to ulama who played various official roles but were not generally muftis.

In the Ottoman Empire, starting from the early modern era, the title came to designate the chief mufti, who oversaw a hierarchy of state-appointed ulama.

The Ottoman Sheikh al-Islam (French spelling: cheikh-ul-islam[note 1]) performed a number of functions, including advising the sultan on religious matters, legitimizing government policies, and appointing judges.

[3] Like other honorific titles starting with the word sheikh, the term shaykh al-islam was in the classical era reserved for ulama and mystics.

[citation needed] Under the Ilkhans, the Delhi Sultanate and the Timurids the title was conferred, often by the ruler, to high-ranking ulama who performed various functions but were not generally muftis.

[2]: 400  For example, the Hanafi scholar 'Ala' al-Din al-Bukhari issued a fatwa stating that anyone who called Ibn Taymiyya "Shaykh al-islam" had committed disbelief (kufr).

After the National Assembly of Turkey was established in 1920, the office of Sheikh ul-Islam was placed in the Shar’iyya wa Awqaf Ministry.

Shaykh al-Islām in different languages
Book cover image, printed in 1906 in Cairo , written on it: Volume II of Tabaqat al-Shafi'iyya al-Kubra by Shaykh al-Islam Taj al-Din al-Subki