The aim of this article is to examine contemporary conceptualizations of cultural and linguistic diversity in the Swedish policy for early childhood education and care (ECEC). The analysis draws on in-depth interviews with high-level policy actors and the analysis of documentary material. Using the concepts of interculturality and hybridity as theoretical tools, the study explores understandings of diversity at preschool and connects these with the role of preschool in culturally and linguistically diverse settings. The findings suggest that the concept of diversity is (a) embedded in dynamic notions of culture, (b) articulated within discourses of democratic citizenship, and, (c) its enactment is promoted in time and space where negotiation and dialogue emerge. Within the context of increased population diversity, there is consensus over the core functions of the Swedish language in preschool, while discourses of multilingualism are characterised by positive yet complex and sometimes diversified constructions. These are reflected in the multiple roles assigned to preschool based on preparing, preventing, and promoting educational and welfare values to children from diverse cultural and linguistic backgrounds.