Infant mortality decline in urban Senegal: The case of colonial Saint-Louis, 1880–1921

Our study utilises vital registers from Saint-Louis, Senegal, between 1880 and 1921 to track trends in infant mortality and to investigate individual-level determinants of neonatal and post-neonatal mortality. We find evidence of sizeable declines in infant mortality rates, begin-ning in the late 1890s. For the individual-level analysis, we sampled five birth cohorts (N = 4,728) to examine how socioeconomic factors—particularly occupational class, French litera-cy, and neighbourhood—were associated with infant mortality risk. Literacy was associated with significantly lower neonatal mortality, but not in the post-neonatal stage, likely reflecting how proximity to colonial health structures shaped reproductive health and infant care. Using interactions, we examined how the effects of socioeconomic factors on mortality may have changed over time. Our analysis suggests that infants from lower socioeconomic backgrounds, as captured by paternal occupation or neighbourhood of birth, faced increasingly higher rela-tive mortality risks compared to those from more advantageous socioeconomic backgrounds.