Scholars of fascist ideology have defined fascism as a political synthesis of revolutionary syndicalism and integral nationalism. The ideological evolution from the far left of Italian fascism, embodied by Benito Mussolini, has already been effectively demonstrated. Considering that recent scholarship of fascist ideology has increasingly emphasized the nationalist or rightist aspect of the fascist synthesis, there is also a need to examine the development of the far right, represented in Italy by Enrico Corradini's Italian Nationalist Association. The evolution of Corradini's thought, however, has not been adequately isolated and analyzed within the specific context of Liberal Italy, nor evaluated in relation to the development of fascism. Corradini's ideology was not only an integral source of the original fascism of 1919, but his doctrine also played a progressively significant role as fascism shifted rightwards and became a mass movement. This article will trace Corradini's ideological development in six historical stages, from 1909, during the second wave of modern nationalism in Italy, to 1923, when the National Fascist Party absorbed the Italian Nationalist Association. It will illustrate how Corradini applied a coherent and proto-fascistic worldview to the turbulent historical events of the period that included the war in Libya, the Great War, and the post-war era, which saw the Liberal regime collapse in the face of internal and external stresses and the onslaught of fascism.