Nizam al-Mulk, Persian scholar and vizier (died 1092)

Abū ʿAlī Ḥasan ibn ʿAlī Ṭūsī, better known by his honorific title of Niẓām al-Mulk, was a Persian Sunni scholar, jurist, political philosopher and vizier of the Seljuk Empire. Rising from a low position within the empire, he became the de facto ruler of the empire for 20 years after the assassination of Sultan Alp Arslan in 1072, serving as the archetypal "good vizier". Viewed by many historians as "the most important statesman in Islamic history", the policies implemented by Nizam ul-Mulk remained the basic foundation for administrative state structures in the Muslim world up until the 20th century.