In 1901, the year the six Australian colonies federated to become one country, revolution was being plotted across the world. Publicised in the newspapers and carried by migrants along global trade routes, the anarchist movement appeared prepared for a long period of power as one of the world's dominant historical forces. In few places was this more evident than in Spain, where poverty and population pressure prompted increasing emigration. In anglophone Australia, governments had long been alert to the threat of radicalised migrants, and this book traces the forgotten lives of one particular group of such migrants, the Spanish anarchists of northern Australia, revealing the personal connections between the English-speaking British Empire and the world of Spanish-speaking radicals. The present study demonstrates the vitality of this hidden world, and its importance for the development of Australia.