This chapter explores how studies of memory open important insights for quantitative researchers who use textual data to model change over time. Understanding how societies see their own past can illuminate dynamic forces acting upon the society. The chapter discusses recent theoretical work in memory studies, in which scholars stress the multiplicity of ways of understanding the past – challenging, for instance, widespread prejudices that handle history as an accumulation of great personalities, ideas, technologies, or other events; and critiquing the “forward momentum of time” as the dominant factor of experience. It lays out a series of case studies designed to apply text mining to highlight how parliamentary speakers constructed narratives of the past through recalling episodes from Britain’s collective history – demonstrating the uses to which memories of the Spanish Inquisition and the 1539 Book of Common Prayer were put throughout the nineteenth century. It applies grammatical analysis to show in more general terms how the abstract past was handled by parliamentary speakers over the century, demonstrating an increasing concern with the rights that Britons held in the past. It argues that text mining can be a powerful tool for analyzing the political life of memory over time.