This book explores the life and deeds of Jacques C?ur, the Merchant Prince of medieval France, examining his rise from humble origins to immense wealth and influence, his pivotal role in financing the French monarchy during the Hundred Years' War, and his eventual fall from grace due to political intrigue and rivalries with the nobility. Through an in-depth analysis of primary sources, including royal correspondence, trial records, and contemporary chronicles, the book delves into C?ur's contributions to the financial systems of his time, highlighting his innovative use of banking instruments such as letters of credit and his role in reshaping the economic landscape of late medieval France. The book also explores the socio-political context of his life, reflecting on the tensions between the bourgeoisie and the feudal aristocracy, the fragile nature of power, and the complexities of loyalty and ambition in medieval court politics. C?ur's cultural patronage, including his architectural legacy in Bourges and his support for the arts, is also examined, showing how his wealth enabled him to influence both the intellectual and artistic currents of his time. Ultimately, this work frames Jacques C?ur's story as a reflection of broader historical shifts?from the rise of merchant capitalism to the changing power dynamics in France?offering timeless lessons on social mobility, innovation, and the precariousness of power. C?ur's life serves as both a symbol of the opportunities and challenges faced by the emerging bourgeois class and a cautionary tale about the fragile balance between personal ambition and the established social order.