Abstract
After a brief assessment of mainstream theories of nationalisms, the article focuses on those that stress boundary mechanisms. The classical division of theories of nationalism into primordialist and instrumentalist approaches is rejected, arguing that at least three more approaches can bring a distinctive contribution to the field: homeostatic, transactionalist and ethno‐symbolist. The article defines nationalism as a process of border creation and/or maintenance. Boundaries are needed to ensure a distinction between two or more groups, or the spaces they inhabit. Hence, in all processes of nationality formation, as well as in all ethnic conflicts, political leaders give a prominent place to the boundaries which define ‘their’ national community. Finally, violence is used to reinforce ethnic boundaries when the latter are particularly weak or under threat.