This article uses techniques of microhistory to explore how Janbai, the third wife of Sir Tharia Topan, exerted economic, religious, and social influence in Indian Ocean networks. An Ismaili woman from a Gujarati trading family who lived in East Africa, Janbai lies outside of the social worlds that have dominated studies of Muslim modernity in South Asia, which centre on Sunni male professionals from North India. Janbai was illiterate and largely disconnected from textual debates about modernity. In fact, she was just the sort of woman that reformers castigated for their supposed attachment to religious superstitions and customary practices. In contrast, studying Janbai through an alternative frame of ‘material modernity’ reveals the complex biography of a women who neither conformed to the idealized ‘new’ woman, nor simply reproduced inherited practices. Instead, she navigated rapid social mobility, shifting geographies, and new technologies and institutions, particularly colonial law courts, in ways that echoed and departed from how women had long exercised agency. The article argues that scholars, by foregrounding textual archives and discursive analysis, have tended to reproduce the marginalization of women like Janbai. In contrast, looking to sources such as jewellery and photographs, and reading textual archives with greater attention to gendered patterns of consumption and investment, brings Janbai from the margins to the centre of our understanding of modernity. In addition to enriching our understanding of the lives of women, increased attention to materiality and visuality opens up critical new avenues for writing a more variegated history of Muslim modernity.