This is a relatively brief, interpretive treatment of the man whom Bakunin called ?the greatest conspirator of the century? but whom most English-speaking scholars know, if at all, as an obscure, misspelled name. This is the only English biography of Buonarroti and the only book in any language to treat him as ?the first professional revolutionist.? It provides a detailed historiographical analysis of recent Italian Buonarrotian research, bearing on a wide variety of different special aspects of modern European history. It throws light on the conspiratorial underground of the early nineteenth century, on the relationship between the French Revolution and nineteenth century radical movements, on the historiography of the French Revolution, and on the development of the ideology of the totalitarian Left. Perhaps the main contribution made by this study is to provide precise factual data on aspects of pre-Marxian radicalism that have been heretofore treated in a vague, overgeneralized fashion. Buonarroti is regarded as the focal point for a preliminary investigation into the origins of an important but neglected profession which developed during the early nineteenth century. In the introduction, a distinction is drawn between the ?amateur? revolutionist?the doctor, lawyer, or merchant who played a prominent role in various particular revolutions?and the frequently unemployed professional who attempted to create a situation that would make possible the practice of his craft and who had a vested interest in ?revolution? in general but did not necessarily play a part in any particular revolution. In the following chapters, the entire course of Buonarroti's long career is surveyed chronologically, in an effort to account for the emergence of this new type of man. He is viewed as a youthful disciple of Rousseau, studying law at the University of Pisa; as a follower of Robespierre who served as a Jacobin agent in Corsica and Oneglia and was granted French citizenship by the National Convention; as a colleague of Babeuf and later author of the classic account of the Conspiracy of the Equals; as a political prisoner during the Empire who was involved in anti-Bonapartist plots; as the arch-conspirator whose agents infiltrated the revolutionary secret societies of Metternich's Europe; as Mazzini's rival in the Risorgimento; and finally, as the patriarch venerated by radical Frenchmen, who indoctrinated a new generation of young Parisians while directing political propaganda and agitation against the Orleanist Regime and reshaping the mythology of the French Revolution. At each of these stages of Buonarroti's career, his ideological orientation is analyzed, his present position in historiography examined, and his actual historical contribution suggested. The concluding chapter offers a reappraisal of the historical significance of Buonarroti's life and work. As a secular fundamentalist who took the words of the eighteenth-century philosophers literally and as a devout Jacobin who had seen in the First Republic his ?heavenly city? materialize on earth, Buonarroti was incapable of coming to terms with the post-Thermidorian world. He achieved a new career by remaining frozen in the heroic pose of 1793 while outliving his times by over four decades. Although he dedicated his life to preparing for the great day that would restore the First Republic and thus shake the world, he failed to accomplish the mission he had set himself. However, he succeeded as a prototype. Others were eventually inspired by his example to adopt a similar vocation, with fateful consequence to all of Western civilization. The study concludes with a bibliographical essay containing a brief note on the probable role of the Italian Communist Party in stimulating Buonarrotian research in Italy and extensive critical discussion of selected scholarly literature on the various phases of Buonarroti's career.