Nizam al-Mulk

Abū ʿAlī Ḥasan ibn ʿAlī Ṭūsī (Persian: ابوعلی حسن بن علی طوسی) (1018 – 1092), better known by his honorific title of Niẓām al-Mulk (Persian: نظام‌الملک, lit. 'Orderer of the Realm'), 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.

One of his most important legacies was the founding of a system of madrasas in cities across the Seljuk Empire which were called the Nizamiyyas after him. He also wrote the Siyasatnama (Book of Government), a political treatise that uses historical examples to discuss justice, effective rule, and the role of government in Islamic society.