ABSTRACT The question of how to symbolize collective identities in an age marked by both nationalist fervor and diversity politics has dominated public debates and highlighted the political role of religion. But what happens to religious objects, sites, and practices when they are framed as cultural heritage? What are the forces behind the ways in which religion is drawn into the dynamics around cultural heritage and heritage-making in secular societies? And why and how do some religious places become iconic sites of cultural heritage, arousing both national sentiments and global concerns? In this article, we explore the complex politics around religion and cultural heritage and scrutinize how they intersect with processes of secularization, and regimes of diversity and secularism. We argue that there is a growing tendency in contemporary societies to culturalize religion, suggesting that the framing of collective heritage is closely linked to what counts as religion and as culture in everyday life and in official discourse. We theorize this dynamic through the concept of ‘heritage religion’ and contend that it offers a distinctive material perspective on the culturalisation of religion. Drawing on Durkheim, we point out how processes of religious heritage-making produce new forms of sacredness.