Legionnaires: Why Modern States Enlist Foreign Soldiers
My book project explains the calculus that has led modern states to recruit soldiers who are neither subjects nor citizens of the government they serve—foreign legionnaires. The book beings by presenting an original dataset of recruitment policies, identifying legionnaire enlistment programs that states have implemented between 1815 and 2020. Drawing on government records in multiple languages, I show how these policies have influenced modern history’s major wars and spanned the globe.
The project details and tests a theory that explains how governments select among this fuller spectrum of manpower options. I argue that the selection of recruitment policies—citizen or legionnaire—is a function of how a state perceives its vulnerability to defeat, as shaped by two variables: the severity of external threats that it perceives, and the degree to which the government faces political costs in mobilizing additional citizen soldiers. I use archival evidence to present four case studies that test my argument across the full range of its independent and dependent variable values: Angola (1974-76), Germany (1935-45), India (1962-64), and the United States (1861-64).