["Population, Space and Place, Volume 32, Issue 3, April 2026. ", "\nABSTRACT\nWhile fertility differentials between ethno‐racial groups are often attributed to socioeconomic or cultural factors, an emerging scholarship emphasises the importance of context for these differentials to occur. This study examines how context‐level ethnic composition (ethnic context) shapes fertility differentials using the case of Xinjiang, China. Contextual data from the 2010 decennial census were linked with individual‐level data from the 2015 micro‐census. Ethnic context was measured by minority share and ethnic diversity, while controlling for key individual and county‐level covariates. Hierarchical Poisson regressions show that minority share is positively associated with the number of children, whereas diversity is negatively associated. Moreover, ethnic diversity significantly reduced the fertility differential: Turks, in contrast to Han, reported lower fertility as local diversity increased and the Turk‐Han differentials narrowed. To interpret these findings, I combined quantitative analysis with a historical reading. I classified four ethnic context ideal types (the Industrial‐military type, the Han immigrant type, the Multicultural type, and the Indigenous type) and used a simple algorithm to pick three representative cases from each ideal type. With these ideal typical cases, I explained how historical processes have created the distinct ethnic contexts that matter for fertility outcomes.\n"]