Spiegel's work focuses on the theory and practice of
historiography, both in the Middle Ages and in the modern era. Her publications on these topics include
The Chronicle Tradition of Saint‐Denis: A Survey (1978),
Romancing the Past: The Rise of Vernacular Prose Historiography in Thirteenth-Century France (1993),
The Past as Text: The Theory and Practice of Medieval Historiography (1997), and
Practicing History: New Directions in Historical Writing after the Linguistic Turn (2005), as well as some sixty articles on medieval historiography and contemporary theories of historical writing. Many of her articles and books have been translated into other languages such as Japanese, French, German, Italian, Hungarian, Spanish and Chinese. Her best known theoretical work is "History, Historicism and the Social Logic of the Text in the Middle Ages," published in the academic journal,
Speculum, in 1990. In this article, Spiegel addresses the challenges that the
linguistic turn poses to the historical profession and offers the "social logic of the text" as an interpretive lens that locates written sources within the social, political and economic currents that shaped the discourse of the moment while simultaneously foregrounding the active nature of the author’s work as he seeks to reconstitute and reshape reality as he writes. Her 1993 monograph,
Romancing the Past: The Rise of Vernacular Prose Historiography in Thirteenth-Century France sought to demonstrate the utility of such an approach to historical sources. ==Research awards and honours==