This thesis explores the role of Hindu merchants in the Portuguese Estado da Índia from 1730 to 1850 and their myriad processes of engagement with the colonial state. It seeks to understand and account for the extent to which Hindu merchants were dominant commercial and political actors in the colonial economy of the Estado, and how they became indispensable mercantile and political actors for the Portuguese colonial state in India. Although their relationship has been one characterised by 'mutual dependency', this thesis is concerned with illuminating the extent to which it was mutually reciprocal by analysing how, why, and to what effect, Hindu merchants sought to profit and derive substantial benefits from their status as Portuguese colonial subjects. The eighteenth century heralded radical alterations in the political, economic and socio-cultural landscape of Portuguese India. Thus, the impact of these structural reforms on its Hindu mercantile community and the dynamics of their responses to it will also be analysed, in order to elucidate the impact of Portuguese colonialism from the ground up. Although the commercial dominance of Hindu merchants has been widely noted, we know little of their modus operandi and the mechanisms and institutions that undergirded their trade. This thesis therefore seeks to examine the full scope of their modus operandi and the influence of family and kinship bonds in order to provide a more systematic and detailed account of their commercial success. Given the fact that the scope of their commercial network went far beyond the boundaries of the Estado, the manner in which they built, consolidated and managed a global network of crosscultural mercantile partners will also be analysed. By examining the dominance and agency of Hindu merchants, it will demonstrate the continued importance and resilience of local mercantile actors in the global economy of the Indian Ocean, adding further nuance to our understanding of the dynamics of European colonialism on the subcontinent, and the complexity of the engagement between Asian and European actors during this period.