It is a routine slapdown used by historians of pre-modern religion against students or colleagues who are incautious enough to ask, for example, whether a particular individual was motivated by religious or by political concerns: aha, we say, those are modern categories, for this period you cannot separate them. It is a pat and not entirely fair argument, but you see the point. Still, we cannot stop ourselves sliding back into those categories. The historiography of the Dutch maritime empire of the seventeenth century – an astonishing, gravity-defying feat of commerce and conquest, conjured up from almost nothing – insists that the Dutch East and West India Companies were robustly secular entities, driven almost entirely by commercial concerns and with only the thinnest veneer of religious conviction. D. L. Noorlander's game-changer of a book proves, however, that in this world religion was neither distinct from nor antagonistic to commerce.

Noorlander's book, based on his Georgetown University doctoral dissertation, is about the West India Company (WIC), the smaller, more short-lived and more openly aggressive of the two Dutch trading companies. (The aggression is the excuse for the book's odd title, which reads like a marketing ploy: it does not really do justice to the contents.) Founded in 1621, the WIC quickly acquired, and lost, a substantial Atlantic empire: it ruled a large chunk of eastern Brazil from 1624 to 1654, held Angola from 1641 to 1648, and established the flourishing North American colony of New Netherland, which fell to the English in 1664. And its ambitions ranged further, including two quixotic but entirely serious attempts to establish footholds on the Peruvian and Chilean coast. By the time that the Company succumbed to bankruptcy in 1674, this empire was reduced to a handful of Caribbean and west African outposts (the refounded Company [1675–1792], whose main business was slave-trading, lies beyond Noorlander's scope). But it also left a rich paper trail in various Dutch archives, which Noorlander has worked through with impressive thoroughness and insight. By asking the generally un-asked question – so, where was Reformed Christianity to be found in the WIC? – he has produced a very compelling answer: everywhere.

Looked at through one eye, the WIC was a saltily commercial venture, a joint-stock company which traded fur, sugar and any other cash commodity available, including African (but not Native American) slaves. It used religion in order to secure domestic support and to build opportunistic alliances, by trying, for example, to turn the Tupi people of Brazil into Protestants as a bulwark against the Portuguese. Looked at through the other eye, the Company was a politico-religious, almost apocalyptic gambit, mobilising Amsterdam's commercial genius to play its part in the global struggle against AntiChrist's evil empire, Spain. It would liberate the peoples of the New World from their Iberian captivity, trading freely with them and bringing them the gift of the true, Reformed religion. To cut Spain's financial lifeline, to build the kingdom of God in the south Atlantic, and to do it all while turning a profit: if such an audacious scheme even half-succeeded, it could only be God's will.

Both stories are true, but Noorlander amasses a mountain of evidence proving that the second one needs, at the very least, to be taken seriously. The Company invested considerable effort and resource into providing plentiful clergy and lay assistants for their colonies. Recruiting them was difficult – the Dutch Republic was a small country, and the dangers and discomforts of colonial work did not always attract the best ministers – but the Company was assiduously selective. The ministers were also under the authority of the classes of Amsterdam and Walcheren, which did not always agree with Company policy, but the two sides generally worked together smoothly enough: plenty of individuals worked across both institutions.

It is not merely that the resources poured into religious provision went beyond any narrow pragmatism: entire projects were underpinned by an essentially religious agenda. The WIC itself was founded as an instrument of economic war with Spain, which was a godly task. The very first WIC expedition, to Brazil in 1623, was set about with apocalyptic prophecies, and the Dutch saw every encounter with Native Americans through what Noorlander calls ‘their self-appointed savior function’ (p. 165). If, during the Company's last twenty years, complaints from churchmen that they were being starved of funds grew louder, it was not because the WIC had lost interest in them, but because it was in slow financial meltdown. ‘The directors did not neglect the church as much as they drove the WIC into the ground and took everything, including the church, with them’ (p. 199).

It may have come to nothing, but it was quite the impressive Calvinist empire while it lasted. Its heart was Brazil, the only WIC colony which established its own classis (albeit not fully independent; there was nothing in the Dutch Atlantic to rival the East India Company's properly self-governing Church at Batavia). The Brazilian Church could not only manage its own affairs without being constantly overruled by well-meaning control freaks in Amsterdam, it could also undertake the WIC's most serious missionary project, to their allies the Tupi. Similar, although smaller-scale and less well co-ordinated, efforts were undertaken in New Netherland, in Angola and Kongo, in Suriname and at Elmina (modern Ghana).

All of these missionary efforts did, however, share one feature: complete or near-complete failure. For all their commitment to the enterprise, there was no real creativity in how it was done, nor any serious attempt to rise above Dutch Calvinism's cultural specificities. A recurrent feature of the failed missions to Native Americans in New Netherland, Noorlander writes, is that ‘no-one ever seems to have considered not asking Indians to memorize the 129 questions and answers of the Heidelberg Catechism’ (p. 187). But this is not simply a failure of imagination. Noorlander places much of the blame on the dead hand of the Amsterdam classis, so paranoid (in the wake of the Synod of Dordt) about doctrinal deviation that it routinely blocked attempts by ministers in Brazil and elsewhere to produce simplified, adapted or even translated catechetical texts. The only consistent missionary method that the Company supported was education, by which they meant, ideally, separating children from their families so that they could be raised in an exclusively Dutch and Protestant environment, before being released back to their peoples to spread the twin gifts of Reformed Christianity and Dutch civility. In 1641 the Brazilian classis hatched a scheme for a Tupi boarding school, ploughing significant resources into buildings and planning before asking any of the Tupi for their opinion. The ministers seem to have been genuinely surprised to learn that Tupi parents had no wish to hand their children over to the Dutch for indoctrination.

It may be discussing a litany of failures, but this book is a triumph: exhaustively researched, written with a light touch and an eye for telling detail, compelling in its arguments and always aware of the bigger picture. (It even has a series of very helpful maps drawn by the author himself.) Noorlander has permanently changed the way in which we will view this subject. Now, could someone please give the Dutch East India Company the same treatment?