Why is Norway not part of the European Union?

The European Union (EU) currently consists of 27 member states. Norway is not among them, which makes it one of the few Western European countries that do not belong to the international organization. How did this anomalous situation come about? The EU evolved out of the European Coal and Steel Community, founded in 1951 with six original member states. This was eventually transformed into the European Economic Community (EEC) and, later, the European Community (EC)....