Abstract: Compares Northern Ireland with a number of other divided societies in Europe, including South Tyrol, Cyprus, and the Hungarian regions of Romania, Slovakia, and Serbia. It argues that states are unlikely to accommodate minorities if their ethnic kin in neighbouring states pursue irredentist claims. An agreement became acceptable to Northern Ireland's unionists only when the Irish republic removed its constitutional claim to Northern Ireland. Alcock also argues that unionists were able to accept the all-Ireland institutions in Northern Ireland's Agreement in the context of similar developments in other parts of the European Union. The chapter is an example of ‘linkage’ politics, i.e. it stresses links between exogenous factors and internal politics.

Keywords: Agreement, constitutional claim, divided societies, Europe, European Union, irredentism, linkage politics, minorities, Unionism,