During the Iron Age, the north and east of France saw the gradual adoption of steel use, followed by a series of key innovations in production methods. The manufacture of iron objects was becoming widespread, reflecting an increase in their consumption and their spread across different social strata. Due to the research carried out on the iron and steel industry in northern France for more than two decades, it is now possible to describe a diachronic evolution of these activities, in their technical, economic and social dimensions. This geographical area saw the emergence of elites at the beginning of the La Tène, from the rise of Celtic art and weaponry in Middle La Tène to the appearance of proto-state structures at the end of the Iron Age. Finally, within this general evolution of the iron industry in the Iron Age, the Hauts-de-France is addressed through an inventory of prehistoric iron working sites and a first chronological synthesis of its evolution, implantation and organisation. The region is also put into its general context by suggesting research projects to be undertaken in this region. Traduction : John Lynch.