Eighteenth-century managers built their illegitimate theatres around the presence of performing animals, but the animals have rarely been a part of theatre histories. This article places horses, the headlining acts and primary draw for London audiences, back into the ring of Astley's Amphitheatre. It examines how the presence of horses such as the Gibraltar Charger, along with the relationships between non-humans and human actors, influenced constructions of political masculinity there. For Philip and John Astley, performances with the Charger in 1788 and 1789 were central to their patriotic constructions and displays of chivalrous, honourable, refined and polite masculinity.