[en] At the turn of the twentieth century, Belgian sociology and Belgian colonialism in Congo developed into a small political and academic elite that shared the same ideological stances. Colonialism played a more significant role. Colonization provided a new stage for emerging disciplines such as geography and sociology – which played their part in creating a brand new Belgo-African ethnology. Despite being a work in progress, sociology (which mainly involved jurists and lawyers) found a key place in the new institutional colonial sciences network. A colonial consensus was reached between Catholic and Liberal elites during the colonial crises and polemics that were also theoretical battles. Colonial sociology aspired to become the encyclopedic ethnology of the last African Terra incognita, as well as the government’s modern science of the indigenous people. Missionaries, colonial magistrates and administrators carried out field research. It gradually generates a significant output on the scale of the social sciences of the time. But it was more closely linked to the institutions of colonial power than to academic institutions. As colonial sociology partially freed itself from the colonial context during the 1950s, under the banner of professional ethnology, on the one hand, and the sociology of development on the other, it had to contend with a dramatic decolonization process. Quite rightly considered colonial sociology but not sociology of colonization, its success can, however, not be summed up in a single ideology. Colonial sociology never was an effective instrument of domination or tool for liberation; it has never entirely succeeded in influencing the dominant institutions and ideologies. The discipline has a rather uneven and unstable timeline due to the physical and moral distance between the field and the Belgian metropolis.