This article proposes an approach to media imperialism from the telegraphic news agencies' point of view. Since the mid-nineteenth century, in fact, Western imperial interests were reflected in the geographical expansion led by the first international news agencies. The War of the Pacific (1879-83) in South America provides an entry point for investigating both the notion of the British 'informal empire' and the role of the first telegraphic news agencies in the South American region. The history of the news agency business in the subcontinent from the 1850s onwards helps contextualize the conflict between the South American republics of Bolivia, Chile and Peru as news agencies, newspapers and other information practices of the time revealed this event in Europe and the rest of the world. By the end of the war, Reuters and Havas (the British and the French news agencies), numbered their own casualties as a consequence of their confrontation in an extra-European region.