In Nothing Happened.  A History (Stanford University Press, 2021) I explore what people really mean when they say "nothing happened," or "nothing is the way it was," or "nothing has changed" -- by looking at how the word "Nothing" is used to express historical consciousness.  Topics include photographs and postcards depicting ruins in postwar Europe; blank books and forms; UrbEx photography; historical landmark signs; When Prophecies Fail; histories of injustices and more.  For an introduction, see my discussion with Peter Fritzsche at the Seminary Coop Bookstore.

Editor, The Cultural History of Memory in the Nineteenth Century (Bloomsbury Publishers, 2020). I authored an introduction that offers an overview of memory in its multitudinous aspects of nineteenth-century cultures, emphasizing the role of new visual technology, particularly photography, in capturing the presence of the past.

Stuff I'm always thinking about: theory and practice of historical representation, including historical consciousness and historical subjectivity; museums and historical preservation; historical narrative; photographs as historical objects; the implicit caption; 19th- and 20th-century German and modern European intellectual and cultural history.