Ibn KhaldunIbn Khaldun (; , ; 27 May 1332 – 17 March 1406) was an Arab sociologist, philosopher and historian who has been described as the precursive founder of the proto-disciplines that would become historiography, sociology, economics, and demography. Niccolò Machiavelli of the Renaissance, Georg Wilhelm Friedrich Hegel and 19th-century European scholars widely acknowledged the significance of his works and considered Ibn Khaldun to be one of the greatest philosophers of the Middle Ages.
His best-known book, the ''Muqaddimah'' or ''Prolegomena'' ("Introduction"), which he wrote in six months as he states in his autobiography, influenced 17th-century Ottoman historians such as Kâtip Çelebi, Ahmed Cevdet Pasha and Mustafa Naima, who used its theories to analyze the growth and decline of the Ottoman Empire. Ibn Khaldun interacted with Tamerlane, the founder of the Timurid Empire. Provided by Wikipedia