The Department of Foundations of Law in the Faculty of Law has organised a meeting of the Maastricht Foundations of Law Colloquia. On 18 September the speaker is Marc de Wilde. His contribution discusses the relation between Hugo Grotius’s theory of alliances with non-Christians and his activities as a legal advisor of the Dutch East India Company (VOC). In his early writings, Grotius defended the right of Christians to enter into alliances with non-Christians, even if they were aimed against other Christians. He thereby provided a justification for the VOC’s alliances with non-Christian rulers in the East Indies, which were aimed against the Spaniards and Portuguese. Although technically a private actor, the VOC had entered into these alliances on behalf of the Dutch United Provinces. Grotius personally drafted a series of letters to East-Indian rulers, in which he explained and justified the VOC’s alliances, including its aspired monopoly on the spice trade. The ideas he developed as a VOC advisor were later incorporated into his magnum opus De iure belli ac pacis, and presented as part of a general theory of alliances and monopoly contracts.