Northern Ireland is part of the United Kingdom, and covers 5,459 square miles (14,139 km²) in the northeast of the island of Ireland, about a sixth of the total area of the island. It has a population of 1,685,000 (April 2001) — between a quarter and a third of the island's total population. It consists of six counties situated within the province of Ulster, and in the UK is generally known as one of its four Home Nations, forming a constituent country of the United Kingdom.The Northern Ireland Act 1998 describes Northern Ireland as "part of the United Kingdom".

Northern Ireland is a constituency of the European Parliament. It currently elects 3 MEPs using the Single Transferable Vote.