In its introduction, the article analyses the polysemous concept of "myth" and the use of the Medieval Age during Italian "Risorgimento". In this context we can study the myth of the emperor Frederick II. For Simonde de Sismondi, he represented the foundation of Italian language and the patronage of the culture. For Vincenzo Cuoco, the emperor Frederick was a model of a "re nazionale". For Gregorio, he made many reforms. For Ugo Foscolo, Frederick defended the State - rights vs the Church and the theocracy. In the second half of XIX century, a negative myth of Frederick II also developed: the reactionary culture regarded the emperor as a model of "Chaesarism" and a persecutor of the Church. Finally, Francesco De Sanctis gets over the mythographical tradition and puts the emperor Frederick in a historical context. Now for the historiography Frederick is not the author of a "missed opportunity" of Italian unity. He integrated a part of Italy in a imperial context.
Keywords: Myth, Frederick II, Italian Risorgimento.