The British Royal Navy of the French Wars (1793–1815) is an enduring national symbol, but we often overlook the tens of thousands of foreign seamen who contributed to its operations. Foreign Jack Tars presents the first in-depth study of their employment in the Navy during this crucial period. Based on sources from across Britain, Europe, and the US, and blending quantitative, social, cultural, economic, and legal history, it challenges the very notions of 'Britishness' and 'foreignness'. The need for manpower during wartime meant that naval recruitment regularly bypassed cultural prejudice, and even legal status. Temporarily outstripped by practical considerations, these categories thus revealed their artificiality. The Navy was not simply an employer in the British maritime market, but a nodal point of global mobility. Exposing the inescapable transnational dimensions of a quintessentially national institution, the book highlights the instability of national boundaries, and the compromises and contradictions underlying the power of modern states.