The nobles who were established in Canada during the French Regime constituted a not so well-known social group. The mere existence of a Canadian nobility was debated by historians during the 1960s and the 1970s and, afterwards, this group sinks almost into oblivion until the beginning of the 2000s. But some recent works are a powerful incentive to examine anew the origins of the nobles of the St Laurent valley and to try to understand their juridical and social particularities amongst the French second order. The social trajectories and the social behaviour of this small number of families show a mutability and a willingness to adapt to their milieu which cast a new light on the evolution of the French nobility as a whole.