This is a biography of Giuseppe Mazzini, a proponent of nationalism and political reform who was instrumental in forging an independent and unified Italy. The author reassesses Mazzini's ideas and offers insights into his life and the political and intellectual world in which he lived. The book is based on scholarship and archival research and reconstructs Mazzini's long years in exile, his friendships with the greatest figures of the age (Marx, Carylye and Bakunin, amongst others) and the political and intellectual world of the mid-19th century. It places the politics of Italian Unification into a comparative and new setting and offers insights into the political culture of the time.