The outstanding qualities of the Galloway horse landrace are referenced in literary sources from the late sixteenth century onwards. Brief, but eloquent and revealing allusions appear in the work of William Shakespeare, Thomas Dekker, Ben Jonson, and other writers with connections to the Tudor, Stuart, Caroline, and Carolean courts. The Galloway nag was sufficiently influential for its name to become a generic widely applied to small horses of a certain type: speedy, enduring, and reliable. This is still the case in the north of England and Australia, where the terms "Gallowa" and "Galloway" continue to be used today. The Galloway contributed to a surprising number of modern horse breeds, including the Thoroughbred, yet few people are aware of its influence. Miriam A. Bibby shows how and why its contribution has been overwritten by other narratives. In doing so, she also reveals previously unexplored sources that indicate the complex role played by the imagined Galloway in Anglo-Scottish relations. Collectively these represent a unique new genre of commentary that she identifies as "Galloway Nag Satire." This is the first major study devoted to the history of the Galloway horse.