What are the elections for?

The elections are to choose 751 Members of the European Parliament (MEPs).

The parliament dates itself back to a parliamentary assembly created by Europe's founding Treaty of Rome, and which first met 56 years ago. But the elections are much more of a recent innovation.

The first members of the European Union's assembly were appointed not elected. Even after the titular creation of a "European Parliament" on paper in 1962 its members were chosen from national parliaments rather than by election.

Direct elections began in 1979.

The European Parliament is the EU's only directly elected institution. The European Commission, a civil service, is run by appointed commissioners. The Council of the EU, the most politically important body in Brussels, is made up of heads of government and ministers who are elected or appointed at a national level.

Who takes part in the European elections?

About 400 million people across the EU's 28 member states are eligible to vote in the elections that begin in Britain and the Netherlands on Thursday May 23 and that continue into the night on Sunday May 26.

The results of all the votes are kept secret, under the threat of a hefty EU fine, until the last voters cast their ballots on Sunday night.