Empires, characterised by cycles of emergence, conquest, domination and decline, have recurring features that suggest a cyclical dimension. With this in mind, we need to analyse the historical lessons that can shed light on the present. The Arab historian Ibn Khaldun, active in the 14th century, developed theories whose relevance remains significant. Professor Gabriel Martinez-Gros, an agrege in history and a specialist in the medieval Arab world, explores Ibn Khaldun's thought and it's enduring influence on contemporary historiography. This biography examines the power relations between wealth and violence, as well as the dynamics between Bedouin and sedentary societies, highlighting the paradox inherent in state power. These analyses encourage us to apprehend the contemporary world through the frameworks of thought forged seven centuries ago. Audiobook. In French.