This book surveys the lives and careers of naval officers across Europe at the height of the age of sail. It traces the professionalization of naval officers by exploring their preparation for life at sea and the challenges they faced while in command. It also demonstrates the uniqueness of the maritime experience, as long voyages and isolation at sea cemented their bond with naval officers across Europe while separating them from landlubbers. It depicts, in a way no previous study has, the parameters of their shared experiences—both the similarities that crossed national boundaries and connected officers, and the differences that can only be seen from an international perspective.