Building on their training and contacts, Iberian men of letters such as Nogueira widened their intellectual horizons. Amid a period of relative peace known as the Pax Hispánica (1601–1621), the expertise of such figures in historical writing was solicited by members of the Republic of Letters interested in Iberian matters. Such intellectual correspondences gave way to debates on politics of conversion and tolerance and the relationship between royal and ecclesiastical power. In the meantime, someone like Nogueira specialized in historical matters and became a source of information for foreign intellectuals who worked on behalf of French, Italian, English, and other powers. This process of specialization fueled the critical political sense of Nogueira while bringing him increasing attention from admirers and critics. At the core of his self-fashioning strategy, Nogueira’s library became a proxy by which he and his critics came to define his status as a mercenary of knowledge. As this status started to become more evident, so too did a strengthening sense of belonging to a mercenary republic.