This article examines how the historian deals with ‘information’ broadly conceived, especially its acquisition, retention and loss. Ammianus details a complex interplay between those who control information and those who must work with an information deficit. Just as this dialogue plays out within the text, however, so too does it with respect to the author's methodology, which dances between the poles of incomplete and complete information depending on circumstance. Ammianus thus becomes an author as hard to pin down as many (...) of his characters, by turns the omniscient narrator and the dumbfounded participant. (shrink)