How small can microhistorians go? The article proposes the advantages of “particle history,” the intense investigation of small, often isolated and dislocated fragments, and how they connect to the worlds to which they once belonged. To demonstrate the method, the article takes a single stand-alone sentence, a colophon, from an early ninth-century manuscript, Brussels, Bibliothèque Royale de Belgique 8216-8218, in which the scribe, one Ellenhart, reports that he copied the book while on a military campaign and supplies the dates of his copying. This evidence leads the author and readers on a journey to reconstruct a military campaign to Hunia (Hungary) in 819, the reasons for that military venture, the nature of the army's travel, and the scribe's role and progress in making his book. But why was Ellenhart there at all and what did he choose to copy while on campaign? To answer those questions the author examines the special character and critical tensions of Carolingian monasticism and why the monk chose the lives and sayings of the desert fathers to copy while on campaign. From a single sentence in an obscure manuscript, a world of associations and connections opens, reminding us that microhistory is not reductive, as is sometimes claimed, but expansive, for when it works it connects its objects of inquiry to wider worlds of meaning and importance.