How did foreign soldiers become political problems for the states they served? This panel argues that foreignness in twentieth-century warfare was not merely a demographic condition but a destabilizing political force. Across three imperial contexts – the U.S.-Mexico borderlands, the Algerian War, and Britain’s wars of decolonization – these papers show how foreign soldiers exposed contradictions at the heart of modern military power.

Ruqaiyah Zarook opens the panel with the life of Cleofás Calleros, a Mexican-born World War I soldier who enlisted in the U.S. Army before formal naturalization and later became a key mediator within Catholic immigration networks in the Southwestern borderlands. Military service offered Calleros a pathway toward civic inclusion, yet it did not resolve the tension between loyalty and recognition. Instead, veteran status and religious affiliation became tools he used to negotiate fragile authority across church and state institutions. In this case, the foreign soldier revealed the limits of belonging in a nation that depended upon migrant labor and service while withholding full acceptance.

Suzanne Kaufman turns to the French Foreign Legion during the Algerian War to examine how foreignness could be turned against empire itself. Long central to French imperial warfare, the Legion’s corps of non-French European soldiers became a site of ideological struggle. Through Frantz Fanon’s newspaper writings, staged interviews with deserters, and international press circulation, the figure of the legionnaire was recast as evidence of colonial illegitimacy and moral collapse. French military archives reveal deep anxiety as foreignness shifted from imperial asset to political liability.

Katya Maslakowski closes the panel by examining British officers in the era of decolonization who fashioned alternative public pathways to military authority when blocked by institutional hierarchies. Figures such as Frank Kitson drew on colonial counterinsurgency experience and turned to speculative fiction and popular memoir to build reputations for expertise. By appealing directly to the public, they transformed foreign battlefields into stages for remaking British military authority. In doing so, they exposed tensions between professional gatekeeping and public legitimacy in a declining empire.

Taken together, these papers argue that foreign soldiers were indispensable to imperial power yet persistently destabilizing. Whether seeking recognition, defecting symbolically, or marketing expertise through colonial experience, they forced states to confront the uneasy relationship between service, citizenship, and authority. By placing foreignness at the center of military history, this panel argues that the foreign soldier was not peripheral to modern warfare but constitutive of its crises – at once essential to imperial power and uniquely capable of exposing its fragility.