Between the fifth century and the first century BC, the area located between the Ebro and Charente River, linking the Mediterranean to the Atlantic, finds itself at the crossroads of different cultural areas: Celtic Gaul, the Iberian Peninsula, Aquitaine, the Greek cities, and also Rome. Due to the lack of literary sources and archaeological data, our knowledge of indigenous peoples living in this area remains fragmentary. This vacuum can be filled by the study of material archeological remains that these communities left us. Also, coinage can provide crucial data because it functions like a privileged proof and witness of the relations between these protohistoric communities. In addition, due to its symbolic value, coinage offers the very reflection of proto-historic societies.In view of the complexity of regional numismatics, this study seeks to analyse the different regional coinages in order to reveal its dynamics (typology, circulation, metrology, chronology, location of discovery, archaeological contexts, etc.).As the coin is the expression of a social context, this work proposes to comprehend the variety of monetary practices by way of a transdisciplinary approach (archaeological, economic, numismatic, statistical and anthropological). One of the central questions remains linked to the appearance of coinage. In this perspective, we are interested in the rhythms, modalities, and agents of its diffusion. The introduction of coins in exchanges implies a whole series of structural changes whose social, economic and political impact we try to measure. On the other hand, an analysis of the different coinages has led us to find characteristics of ethnic realities, trade flows, political and cultural changes, as well as influences from more distant environments. This approach has also allowed us to distinguish historical trends, as well as singular cultural domains.More broadly, the research focuses on the role of money in these protohistoric societies: what role does it play, what is its importance? Who and what it serves? These questions aim to better understand the terms of trade in the Second Iron Age.For the first time, this research outlines an intelligible monetary and economic panorama in-between the first appearance of coins and the establishment of the Roman monetary system.