According to traditional diplomatic history, during Eighteenth century the European States strengthened their control over the diplomatic apparatus and make it an instrument increasingly aligned with national interests. But the new diplomatic history has questioned this traditional modern State’s narrative and has drawn a more multifaceted picture. On the basis of this challenge, this paper aims to demonstrate, through the letters of French consuls in Spain in 1761/1762 stored in the Diplomatic Archives of Nantes, how the diplomatic apparatuses of different European and non-European States, and even private agents, could help each other to pursue interests and to achieve goals of various historical actors. The result is the picture of a permeable diplomacy with porous borders, but even with its limits.
