In the hours after the Brexit result was announced, anti-Brexit politicians in Belfast vowed to fight it. The majority of people in Northern Ireland had voted to remain in the European Union, in contrast with the rest of the United Kingdom. "The British government has no democratic mandate to represent the views of the North," said Gerry Adams, president of the Sinn Féin party, which has long opposed British rule of Northern Ireland.

Before long, some international observers were predicting the worst; that Brexit would disrupt the fragile status quo in Northern Ireland and reignite the old Northern Ireland conflict, which for decades saw pro-UK unionists and anti-UK republicans fight each other on the streets. Of particular concern to politicians and locals is the status of the border between Northern Ireland and Republic of Ireland. Today, the border is open and barely noticeable — but when Britain leaves the European Union, that border will become the EU's new frontier. Some worry that controversial military checkpoints will be reintroduced.