Growing numbers of sailors powered British fleets during the long eighteenth century. By exploring mariners' habits, dress, and material practice when in port, this article uncovers their roles as agents of cultural change. These men complicated material hierarchies, with a broad impact on developing western consumer societies, devising a distinctive material practice. They shaped important systems of transnational exchange and redefined networks of plebeian material culture. Mariners were also endowed with a growing rhetorical authority over the long eighteenth century, embodying new plebeian cosmopolitanism, while expressing facets of a dawning imperial masculinity. Marcus Rediker described eighteenth-century Anglo-American mariners as plain dealers, wageworkers, and pirates, as well as “men of the world.” This international contingent mediated between world communities, while demonstrating new tastes and new fashions. They also personified the manly traits celebrated in Britain's burgeoning imperial age.