This article investigates the modern history of genealogy through the lens of keyword indexesan essential resource for access to genealogical information. Empirically, the article studies the role of indexes in Euro-American genealogy from the nineteenth century to today. Particular attention is paid to the 1960s-2010s, when genealogy changed through growing popular engagement, new technologies, rising and falling academic interest, and increased commercialisation. Focusing on a set of grassroots cases from Sweden that have been crucial to the subfield of Swedish-American genealogy, the article explores the work of local Swedish heritage societies and the dream of empirical 'totality'; the cooperation between heritage societies and academic historians; the impact of microfilm and digital technologies in creating a sense of information overload; the economy of unpaid volunteer and state-subsidised labour; and how paper-based indexes, created largely through grassroots initiatives, have been transformed into digital commodities on an international genealogical market. While this is an important enquiry for understanding the history of genealogyone of the most widespread popular pursuits in modern historyit also addresses the intricate relations between grassroots initiatives, academic research, and capitalism in modern archive history.