Secularism—i.e., the separation between the state and religious institutions—is a fundamental characteristic of liberal democracies, yet support for secular arrangements varies significantly across Western countries. In Canada, such attitudinal divergences are observable at the regional level, with citizens from Quebec displaying higher levels of support for secularism than other Canadians. In this paper, we test three hypotheses to account for this regional discrepancy: religiosity, liberal values, and out-group prejudice. Using data from an online panel survey (n = 2,000), our findings suggest that support for secularism in Quebec is mostly explained by the province's lower baseline levels of religiosity, anticlerical feelings, and by its distinctive understanding of liberalism. These factors are likely to result from Quebec's unique religious and sociohistorical history. Results also suggest that while negative feelings toward religious minorities are positively correlated with support for secularism across the entire country, negative feelings toward ethnic minorities are associated with lower support for secularism in Quebec. These findings disprove the commonly held assumption according to which support for secularism is driven by ethnic prejudice in Quebec.