In recent years, the European Union (EU) has devoted unprecedented resources to containing West African migrants in Mauritania. Within certain segments of the country’s ‘Arab Moor’ population, these efforts have stirred fears of demographic replacement. While EU external migration policy is a relatively new public question in Mauritania, this is not the first time that the relationship between migration and ethno-racial identity has figured in public debate. In the early 1970s, an underground movement in Mauritania, named the Kadehine (‘the toilers’ in Arabic), presented a scathing critique of dominant perspectives on West African labour migration to the country, which tended to depict Black migration as a threat to Arab Moor identity. From the perspective of the Kadehine, such divisions were part of a ruling-class strategy of dividing workers. Based on oral history interviews and archival research, this project explores how the Kadehine and associated movements viewed the relationship between migration and inequality in the country, asking whether this vision holds any lessons for today. How, for instance, was migration analysed in relation to class, race, and gender-based inequality? And how did this analysis relate to the movement’s broader strategic vision for the future of the country and region? What can be learned from this vision, given the unprecedented public attention that now revolves around migration in Mauritania? In exploring these questions, this project treats the Kadehine and the broader movement from which they emerged as a source of theory in their own right.