This essay considers what big data has to offer the field of theatre history. In particular, it applies data visualization to the study of Yiddish theatre between the two world wars, and argues that data visualization offers an important corrective to how Yiddish theatre has traditionally been regarded by theatre historians. Visualizing the data from Yiddish theatre programs and ephemera reveals how hundreds of individuals who scarcely appear in twentieth-century theatre history were in fact influential figures. Furthermore, the essay argues that sources like theatre programs, cast lists, and correspondence are valuable repositories of historical data and ought to be evaluated as such. It demonstrates how compiling, aggregating, analyzing, and visualizing the data contained in these sources can offer new perspectives on the conventional wisdom of theatre history: its key figures, its major events, and its dominant narratives about historical significance.