In which year did the UK join the European Union?

The European Union (EU) is a political and economic union of 27 member states that are located primarily in Europe. The union has a total area of 4,233,255.3 km2 (1,634,469.0 sq mi) and an estimated total population of about 447 million. An internal single market has been established through a standardised system of laws that apply in all member states in those matters, and only those matters, where the states have agreed to act as one. EU policies aim to ensure the free movement of people, goods, services and capital within the internal market; enact legislation in justice and home affairs; and maintain common policies on trade, agriculture, fisheries and regional development.

In 1973, the communities were enlarged to include Denmark (including Greenland, which later left the Communities in 1985, following a dispute over fishing rights), Ireland, and the United Kingdom. Norway had negotiated to join at the same time, but Norwegian voters rejected membership in a referendum. In 1979, the first direct elections to the European Parliament were held.