The project aims to study the development of identities of the nobility space Saar -Lor- Lux and their interactions for. It is organized around three problems, social, cultural and political. This reflection involves first defining the noble group studied and the development of its specific characteristics. The region should be considered as a social space, which underlies the analysis of the totality of social relations in which nobles are engaged, combining sociological and anthropological approaches. Lineage practices and kinship structures will be explained. Operating in an area of contacts and exchanges at the limit of Germanic and Romance areas, this nobility must then be subject to questioning its scriptural, cultural and linguistic practices. A cultivated class likely plays a notable role in the dissemination of cultural models from France to the Empire and can give birth on the steps of a mixed culture. Finally, it is the political attitude of the nobility who receive attention, including its behavior against other political forces in the region are the cities and princes, who regard it as the main obstacle to the transition to the modern state. The last two centuries of the medieval period are marked by great social, economic and political upheavals, the nobility would have at once suffered and enjoyed. Reversing the problem, that is to say from the point of view of the nobility rather than the prince, he will reinterpret their reactions in terms of its social and stately concerns.