Exploration, trade and conquest expanded and upset traditional worldviews of early modern Europeans. Christians saw themselves confronted with a largely heathen world. In the wake of Iberian colonization, Jesuits successfully christianized heathen populations overseas. In his De conversione Indorum et gentilium, Johannes Hoornbeeck presents a systematic overview of every aspect of the missionary imperative from a Reformed Protestant perspective. The most attractive part of his book may be the global survey it offers of the various types of heathens, an early example of comparative religion....