How Irish Unity Got a Boost From Brexit and Demographics

In May 1921, the island of Ireland was split in two, giving rise to Northern Ireland as part of the U.K., and to what would become the independent Republic of Ireland. A century later, the idea that reunification could happen one day has taken on new life. There’s little prospect of the referendum that would bring it about being held in the near future, but shifting demographics, coupled with the forces unleashed by Brexit, suggest a ballot one day is possible -- assuming the British government chooses to hold one.

The 1921 partition was cemented by a peace agreement between British authorities and Irish rebels seeking independence after centuries of British rule. Northern Ireland, with a majority Protestant population (most descendants of settlers from Britain), remained part of the U.K. The largely Catholic southern part of the island became the Irish Free State, before formally declaring a republic in 1949.