Ibn Khaldun (27 May 1332 – 17 March 1406, 732–808 AH) was an Arab Islamic scholar, historian, philosopher, and sociologist. He is widely acknowledged to be one of the greatest social scientists of the Middle Ages, and considered by a number of scholars to be a major forerunner of historiography, sociology, economics, and demography studies.

His best-known book is the Muqaddimah or Prolegomena ("Introduction"), which he wrote in six months as he states in his autobiography. It later influenced 17th-century and 19th-century Ottoman historians such as Kâtip Çelebi, Mustafa Naima and Ahmed Cevdet Pasha, 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.

He has been called one of the most prominent Muslim and Arab scholars and historians. Recently, Ibn Khaldun's works have been compared with those of influential European philosophers such as Niccolò Machiavelli, Giambattista Vico, David Hume, G. W. F. Hegel, Karl Marx, and Auguste Comte as well as the economists David Ricardo and Adam Smith, suggesting that their ideas found precedent (although not direct influence) in his. He has also been influential on certain modern Islamic thinkers (e.g. those of the traditionalist school).

Ibn Khaldun's life is relatively well-documented, as he wrote an autobiography (التعريف بابن خلدون ورحلته غربا وشرقا, at-Taʻrīf bi-ibn Khaldūn wa-Riḥlatih Gharban wa-Sharqan; Presenting Ibn Khaldun and his Journey West and East) in which numerous documents regarding his life are quoted word-for-word.

Abū Zayd 'Abdu r-Rahman bin Muhammad bin Khaldūn Al-Hadrami, generally known as "Ibn Khaldūn" after a remote ancestor, was born in Tunis in AD 1332 (732 AH) into an upper-class Andalusian family of Arab descent; the family's ancestor was a Hadhrami who shared kinship with Wa'il ibn Hujr, a companion of the Islamic prophet, Muhammad. His family, which held many high offices in al-Andalus, had emigrated to Tunisia after the fall of Seville to the Reconquista in 1248. Although some of his family members had held political office in the Tunisian Hafsid dynasty, his father and grandfather later withdrew from political life and joined a mystical order. His brother, Yahya ibn Khaldun, was also a historian who wrote a book on the Abdalwadid dynasty and was assassinated by a rival for being the official historiographer of the court.

In his autobiography, Khaldun traces his descent back to the time of Prophet Muhammad through an Arab tribe from the south of the Arabian Peninsula, specifically the Hadhramaut, which came to the Iberian Peninsula in the 8th century, at the beginning of the Islamic conquest: "And our ancestry is from Hadhramaut, from the Arabs of Arabian Peninsula, via Wa'il ibn Hujr also known as Hujr ibn 'Adi, from the best of the Arabs, well-known and respected." (p. 2429, Al-Waraq's edition).

Ibn Khaldun's insistence and attachment to his claim of Arab ancestry at a time of Berber dynasties domination is a valid reason to believe his claim of Arab descent.

His family's high rank enabled Ibn Khaldun to study with prominent teachers in Maghreb. He received a classical Islamic education, studying the Quran, which he memorized by heart, Arabic linguistics; the basis for understanding the Qur'an, hadith, sharia (law) and fiqh (jurisprudence). He received certification (ijazah) for all of those subjects. The mathematician and philosopher Al-Abili of Tlemcen introduced him to mathematics, logic, and philosophy. He studied the works of Averroes, Avicenna, Razi and Tusi. At the age of 17, Ibn Khaldūn lost both his parents to the Black Death, an intercontinental epidemic of the plague that hit Tunis in 1348–1349.