At the close of a manuscript containing French translations of De regimine principum and De re militari, a note reads: 'Cest liure est A moy homfrey duc de gloucestre du don messieur Robert Roos chevalier mon cousin' [This book belongs to me, Humfrey Duke of Gloucester, a gift from Sir Robert Roos, knight my kinsman]. 1 The early fifteenth-century volume from France was one of Humfrey, duke of Gloucester's many books in French. Robert Roos, Duke Humfrey's former ward and older brother to poet Richard, served in various capacities as a soldier and ambassador in France during the Hundred Years War. 2 This closing annotation witnesses an exchange between two men bound by familial and martial ties; it says nothing about the text nor the context of the exchange. Instead, it stresses the French book's status as a gift from one Englishman to his former guardian.During the Hundred Years War, books like this manuscript circulated between England and the Continent, crossing the Channel through various means: Henry V, for example, took 110 books from libraries in the captured city of Meaux in 1422. 3 His brother John, Duke of Bedford purchased 843 volumes that previously formed Charles V and Charles VI's royal library in 1425. 4 Other individuals commissioned and gifted continental books, like John Talbot, who presented Margaret of Anjou with a miscellany of French texts in 1445, and English patrons who ordered books of hours from Northern France. 5 English men and women visiting and living on the Continent purchased items from local artisans. 6 Similarly, English books crossed the Channel in the other direction. Charles d'Orléans owned an English-made manuscript of John of