European integration is the historical and continuing process through which European states have developed increasingly close economic, political, legal and institutional relationships. It is broader than the European Union because the process began before the EU was formally created and has involved institutions and agreements that are not identical to EU membership. Its central objective has varied over time, encompassing peace, economic reconstruction, trade liberalisation, political cooperation, common regulation, mobility and collective action.
Modern European integration is particularly associated with the European Communities and their transformation into the European Union. The process began with relatively specific areas of cooperation, notably coal and steel, and progressively expanded into a common market, broader policy coordination and a complex institutional and legal order. The European Coal and Steel Community emerged from the 1950 Schuman Declaration and the 1951 treaty involving six founding states. European integration is therefore a process rather than the name of one organisation or one treaty.
The origins of postwar European integration are strongly connected with the experience of war and economic disruption. The Schuman Declaration proposed pooling French and West German coal and steel production under a common authority, placing strategically important industries within a shared framework. The European Coal and Steel Community entered into force in 1952 and represented the first major supranational European organisation.
Its institutional structure included a High Authority, Common Assembly, Special Council of Ministers and Court of Justice, which provided foundations for later European institutions. The idea was not simply to increase trade but to create practical interdependence in areas closely connected with industrial and military capacity. The approach reflected a belief that institutional cooperation could make conflict materially more difficult and establish habits of negotiated cooperation among states that had recently been at war.
European integration then expanded through the Treaties of Rome of 1957, which created the European Economic Community and European Atomic Energy Community. The economic community sought to create progressively closer economic relationships, while later agreements addressed the removal of internal barriers and the creation of common policies. The Single European Act accelerated the programme of completing the internal market, and the European single market became operational in 1993. It provides for free movement of goods, services, capital and people.
The Maastricht Treaty of 1992 created the European Union and added important political and monetary dimensions, including European citizenship and the framework that led to the euro. Subsequent treaties, particularly Amsterdam, Nice and Lisbon, altered institutions, voting procedures and areas of competence. Integration therefore developed through successive treaty revisions rather than through one founding constitutional event.
A major characteristic of European integration is the interaction between intergovernmentalism and supranationalism. Intergovernmental cooperation leaves governments as the principal decision makers and often emphasises unanimity or national control. Supranational integration creates common institutions with authority to act within defined treaty powers, sometimes independently of individual national governments. The EU combines both models.
The European Council represents national leaders and determines broad political direction, while the Commission proposes legislation, Parliament and the Council adopt legislation in many fields and the Court of Justice interprets EU law. This institutional mixture distinguishes European integration from a simple alliance. It also explains why integration debates frequently concern sovereignty, democratic accountability, institutional legitimacy, legal authority and the appropriate balance between national and European decision making.
European integration has an economic dimension extending beyond tariff reduction. The creation of common standards and the removal of non tariff barriers can allow businesses to operate across national markets without complying with entirely separate regulatory systems. The single market's four freedoms facilitate cross border economic activity and individual mobility. Integration also involves competition policy, consumer protection, environmental standards, regional development, research, transport, energy, agriculture and other fields.
Some of these policies require common rules because divergent national measures can undermine a shared market. Others involve coordination because national policies can produce effects across borders. Integration therefore often develops through the practical recognition that certain policy problems are difficult to manage efficiently when neighbouring states operate entirely separate systems.
European integration is not synonymous with the EU. The Council of Europe, for example, is a separate international organisation focused substantially on human rights, democracy and the rule of law. The European Economic Area extends much of the EU single market to Iceland, Liechtenstein and Norway without making those countries EU members. The Schengen Area concerns passport free travel arrangements and includes some countries outside the EU.
The euro area consists only of EU members that use the euro, while some EU members retain national currencies. These distinctions demonstrate that European integration has several overlapping circles and institutions. A country can therefore participate in significant forms of European cooperation without belonging to the EU, while EU members can participate differently in specific integration arrangements.
European integration has produced major institutional and economic interdependence, but its development has also involved disagreements and limits. Governments have differed over the speed and depth of integration, the distribution of powers, monetary policy, enlargement, migration, fiscal coordination, external relations and constitutional questions. Economic integration can create opportunities through larger markets and common rules but can also produce adjustment pressures between sectors and regions.
Common institutions can make collective action possible but also create debates about democratic accountability and national autonomy. Enlargement has extended the geographical reach of the European project while increasing differences in economic structures, political systems and policy priorities. These tensions are not evidence that integration has one predetermined outcome; they demonstrate that integration is an evolving political and legal process shaped by treaties, national decisions, institutional practice and changing circumstances.
The contemporary meaning of European integration therefore encompasses a long historical process of building common institutions and reducing barriers among European states. Its development can be understood as movement from sector specific cooperation towards broader economic integration and then towards a wider political and legal framework, although the process has never been completely linear. The EU remains its most developed institutional expression, with 27 member states and a complex system of institutions whose powers are defined by treaties. European integration also remains broader than the EU because European states cooperate through multiple overlapping organisations and agreements. Understanding the concept requires attention to the difference between geographical Europe, political cooperation, economic integration, legal integration and the specific constitutional system of the European Union.
