European Integration - An Overview European Union, the European organisation dedicated to increasing economic integration and strengthening cooperation among its member states. The European Union was established on November 1, 1993, when the Treaty on European Union or Maastricht Treaty, was approved by the twelve members of the European Community (EC); Belgium, Denmark, France, Germany, Great Britain, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, and Spain. Upon agreement of the treaty, the countries of the EC became members of the EU, and the EC became the policy-making body of the EU. Under the Treaty on European Union, European citizenship wa