The article is devoted to the problems of legitimacy of anti-government protests and the new power coming on a wave of radical mass forms of social protest both from the point of view of legitimization of a protest, and from the point of view of constant search of the legitimate bases for the new power. History of formation of the principles of legitimacy of the power in science, and also transfer of these principles to the field of radical mass forms of social protest, overthrow of the power and formation new is observed. The author considers the principle of the Euhemerus and an euhemerization which is put forward in psychology as important categories and for political science, especially in the sphere of problems of legitimization and the ideology providing it.