Nationality claims are often seen as zero‐sum politics involving incompatible conceptions of the polity. Nationalism and self‐determination are seen as equivalent to separatism. Rethinking the concepts of nationality, self‐determination, and sovereignty and placing them in a historic context allows us to treat them as more tractable and as a form of politics. This is done through a study of the UK, Spain, Belgium, and Canada. Traditions of shared sovereignty are rediscovered. Analysis of the demands of minority nationalisms shows that these do not always entail separate statehood. Public opinion is more open than often assumed. Asymmetrical constitutional arrangements provide a means of accommodating plural national claims. The emerging European polity is a model for a post‐sovereign order in which legal pluralism and constitutional diversity can accommodate multiple nationality claims.