In 1937, French colonial soldiers fired on a crowd of workers assembled during a mass strike in Tunisia’s Gafsa phosphate mines. 18 workers were killed, and many more were injured. These workers had been advocating for better social-environmental conditions, including higher wages, access to potable water, and guarantees for health and hygiene. Today, their names are inscribed in the built environment of Gafsa’s largest mining town, at the center of a monument to the martyrs of the national struggle, and alongside the names of those killed in the armed anti-colonial uprising almost two decades later. The organizational strategies Gafsa’s mineworkers used to mobilize in 1937 mirrored their survival strategies for coping with injury and death in the massacre’s aftermath. Drawing on workers’ testimonies, archived documents from the colonial state, and the built environment of the martyrs’ monument, I argue that an analysis of labor organization in 1937 requires centering questions of embodiment. This paper explores “capacity” in labor movements in a dual sense: the organizational capacity workers developed to mobilize for change, and the embodied capacity workers lost through colonial-industrial repression, when their broken bodies denied possibilities for future wages from manual labor. To understand how Gafsa’s workers navigated existing institutions to build a mass movement in 1937, we also need to understand how they and their families navigated these same institutions to deal with corporeal ruination in the strike’s aftermath. Both of these “capacities,” organizational and embodied, explain the 1937 movement’s ongoing presence in struggles for rights decades later. Gafsa’s labor organizers took advantage of new mobilization possibilities after the Front populaire, a coalition of communist and socialist parties, won election in France in 1936. They joined the dominant French-led trade union, but they defied the union’s French leadership by calling the 1937 strike. French union leaders scrambled to catch up after the massacre, sending a doctor to supervise the colonial state’s investigation of the workers’ injuries. Workers recalled the embodied experience of injury in ways that drew on institutional processes for support while contesting the investigation’s very premises. Their families filed petitions for workplace accident compensation, seeking restitution for lost potential income from manual labor. These linkages between organizational and embodied capacity were folded into the monument in Gafsa, ultimately undermining the post-independence regime’s attempt to transform the massacre’s history into a classless national epic.