The work examines the problem of the evolution of the concept of “national idea” in the works of French conservatives of the 19th century. The author defines the concept of “national idea” as a dual unity of the Rousseauian concept of popular representation and romantic constructions of an “irrational community” based on language and blood. This phenomenon was initially alien to French conservatives. However, in the process of the evolution of their views, they adopted nationalist ideas, turning them into an integral part of the conservative worldview. The work is addressed to specialists in the field of history, political science and all readers interested in the problems of nationalism and European socio-political thought of the 19th - 20th centuries.