This dissertation examines the sixth-century historian Procopius' engagement with the ancient, especially Roman, past in his eight-volume History of the Wars of Justinian. Procopius wrote in a classicizing style that originated with Herodotus and Thucydides a millennium earlier, and yet constructed a work that was both assiduously concerned with contemporary matters, and made an impassioned argument for the importance of the classical past. I examine the many ways in which Procopius engages with memory, applying theories of social memory to help us understand better Procopius' memory-related goals and techniques. This demonstrates not only what memory studies can add to our study of Procopius, but what the study of Late Antiquity can add to our understanding of the functioning of social memory. I use "historical memory" to indicate both the memory of the genre of historiography, and contemporary social memory preserved and transformed by a work of history. The study begins with an introductory Chapter 1, which covers historical and theoretical background, then analyzes Procopius' own introductory prologue. The collection and discussion of the many types of Procopius' references to and engagements with the ancient past follows, with Chapter 2 examining the intertextual references (including a study of Procopius' "rhetorical asides") and Chapter 3 examining the textual. Here, I look at his citations of specific past eras, persons, or events (historical and mythic), as well as comparisons of past and present and presentation of the effects of time: both loss and preservation. Among the themes that are revealed in this analysis is an overarching concern of Procopius' with the specifically Roman past, and in Chapter 4 I turn to examine Procopius' presentation of Rome, Romans, and Roman-ness in more detail. I chart his changing use of the identifier "Roman," as well as his use of other ethnic monikers, and the central position the city of Rome plays in the text's remembering. The concluding Chapter 5 re-considers key themes and passages in the light of the work of Aleida Assmann, Alan Megill, and Pierre Nora, among others, and situates Procopius in the context of the remembering of sixth-century Constantinople.