History of the European Union

We explore the history of the European Union, its characteristics, and main events. In addition, we discuss the current state of affairs.

The European Union was established in 1993, following a long integration process.

What is the European Union?

The European Union (EU) is an organization of European countries functioning as a community with shared economic, social and political interests. It has its own institutions, and consists of 27 member countries, several of which have adopted a common currency (the euro).

The history of the European Union begins with the establishment of the European Coal and Steel Community (ECSC) in 1951, and in particular, with the emergence of the European Economic Community (EEC) in 1957, and the European Atomic Energy Community (EURATOM).

However, the European Union as it is known today was formally established with the Treaty on European Union signed in Maastricht in 1992, which came into force in November 1993. Since then, other treaties have amended some of the provisions of the Maastricht Treaty, and today, the constitutional basis of the European Union is the Lisbon Treaty (signed in 2007 and in force since 2009).


  • The European Union (EU) is an economic and political alliance, currently comprising 27 European countries.
  • Its creation was part of a lengthy process in which some countries joined while others withdrew.
  • The EU was established in 1993, evolving from an earlier organization, the European Economic Community, which emerged after World War II, principally to rebuild and strengthen the economies of Europe following the devastation caused by the war, and to maintain political cooperation among nations and avoid future conflicts.

The Treaty of Rome (1957)

The first steps towards European integration were the signing of the Treaty of Paris (1951), which gave rise to the European Coal and Steel Community (ECSC), and especially the Treaties of Rome (1957), coming into force on January 1, 1958, which created the European Economic Community (EEC) and the European Atomic Energy Community (EURATOM).

The EEC was basically a customs union that allowed the free movement of goods among the six member countries (France, Belgium, the Netherlands, Luxembourg, West Germany, and Italy). Additionally, it implemented the Common Agricultural Policy (CAP), which applied protectionist measures for producers within the member countries.

The institutions created by the Treaties of Paris and Rome had a supranational character, dealing with matters affecting the EEC: the European Commission, the Council of Ministers (or simply the Council), the European Assembly (later the European Parliament), the Court of Justice of the European Communities, and the European Economic and Social Committee.

In 1973, the European Economic Community was enlarged through the accession of the United Kingdom, Denmark, and Ireland, and in 1981 and 1986 Greece, Spain and Portugal also joined.

This period also saw the creation of the European Council (regular meeting of the heads of state and government of the member states), the implementation of the European Monetary System (EMS) alongside the ECU (European Currency Unit, predecessor of the euro), the first elections by universal suffrage for the European Parliament, and the signing of the Schengen Agreement for the gradual elimination of borders (initially between five countries, later joined by the majority of the member states).

In 1984, the European Parliament approved the "Draft Treaty establishing the European Union" (known as the Spinelli Project). This draft proposed to replace the Treaty of Rome with a new treaty aimed at greater European integration. Although rejected by the governments of the member states, this draft spurred the discussions that led to the Single European Act (1986) and the Treaty on European Union (1992).

The road to the Treaty on European Union

Single European Act (1986)

Jacques Delors was one of the main proponents of the European Union.

The Single European Act was approved in 1986 and entered into force on July 1, 1987. It was the first revision of the treaties that had created first the ECSC and later the EEC.

The major changes introduced by the Single European Act are as follows:

  • It established the existence of the European Council (i.e. the regular meeting of heads of state and government) as the body where major political negotiations between member states take place and where major strategic decisions are made. The powers of the European Parliament were also slightly strengthened.
  • It adopted a decisive provision aimed at the gradual establishment of a single market over a period to conclude on December 31, 1992, with the consolidation of an area without borders in which the free movement of goods, people, services, and capital would be assured. This aspiration was embodied in 282 concrete measures and was achieved within the designated deadline.
  • It laid down measures to coordinate the monetary policy of member states, thus paving the way towards the Economic and Monetary Union.
  • It approved several initiatives to promote integration in the field of social rights (health and safety of workers), research and technology, and the environment.
  • It agreed upon the reform of the so-called Structural Funds: the European Agricultural Guidance and Guarantee Fund (EAGGF), the European Social Fund (ESF), and the European Regional Development Fund (ERDF), aimed at achieving greater economic and social cohesion.

Consequences of the Single European Act (1986-1989)

The Single European Act constituted a major step in the integration process. The central figure was the president of the European Commission, Jacques Delors. This French socialist politician promoted the Economic and Monetary Union (a key element in the integration process). In addition, in order to balance the benefits that mainly employers would gain, he proposed the approval of a Social Charter that would guarantee minimum labor and social conditions for European workers.

On the other hand, since the early 1980s, the British Prime Minister, Margaret Thatcher, had been known for her anti-European integration policies, and had fought to achieve a reduction in Britain’s contribution to the EU budget (which she secured in June 1984).

Delors, nonetheless, continued to call for the acceleration of the European integration process, especially in light of the events that began to unfold in Central and Eastern Europe in 1989.

The EEC in the face of the collapse of the Soviet bloc (1989)

The year 1989 saw the collapse of the communist systems in Central and Eastern European countries (the former "people's democracies" that made up the Soviet bloc).

The most symbolic event was the fall of the Berlin Wall on November 9, 1989, followed by the disintegration of the Soviet Union in 1991. That same year, the division of Yugoslavia sparked a new war in Europe, after a period of peace that had begun in 1945.

The first consequence of these events was the reunification of Germany in October 1990. The Federal Republic of Germany, with 80 million inhabitants and 30 % of the EEC's Gross National Product, became an economic power surpassing France and the United Kingdom.

French President François Mitterrand gave new impetus to the European integration process to prevent Germany from emerging once again as a hegemonic power in the region. German Chancellor Helmut Kohl also supported integration to overcome the mistrust generated in France and the United Kingdom by a reunified Germany.

The "power vacuum" created in Central and Eastern Europe with the fall of communism allowed the EEC to be viewed as an organization that guaranteed stability amidst a turbulent Europe. In fact, the new democracies emerging in the countries that abandoned communism began to negotiate their accession to the European Community.

Economic and Monetary Union (EMU) and Political Union (EU)

The acceleration of the European integration process was also driven by an economic factor: the financial and monetary instability that characterized the period. The 1987 stock market crash impacted the world's main stock exchanges, and the problems of the European Monetary System (EMS) led to a crisis in 1992: the British pound and the Italian lira had to exit the EMS, while the Spanish peseta and the Portuguese escudo were forced into devaluation.

All these factors (both political and economic) brought about a major step forward on the road to European integration: the Treaty on European Union.

In 1989, under the initiative of Delors, an Intergovernmental Conference (IGC) was convened to address the final adoption of the Economic and Monetary Union. In 1990, another IGC was convened to study the establishment of a political union.

After nearly three years of discussions, the European Council held in Maastricht (Netherlands) approved the Treaty on European Union, popularly known as the Maastricht Treaty, on December 9 and 10, 1991. The treaty was signed on February 7, 1992 and came into force on November 1, 1993.

Treaty on European Union (1992)

The Treaty on European Union (TEU), also known as the Maastricht Treaty after the city where it was signed on February 7, 1992, amended the pre-existing treaties to foster political as well as economic unity. It entered into force on November 1, 1993.

The Maastricht Treaty formalized the name "European Union", replacing the term "European Community". Among the most significant innovations it introduced with respect to previous treaties were:

  • The recognition of European citizenship to any national of a member state.
  • The creation of the Economic and Monetary Union (EMU) with the aim of eliminating national currencies and establishing a single currency (the euro), which was introduced on January 1, 1999 as the official currency in eleven countries.
  • The creation of the Cohesion Fund to finance projects (in environmental and transport infrastructure matters) in the less prosperous member states.
  • Cooperation in transportation, industry, agriculture, education, research and technological development, and environmental policies.
  • The creation of institutions, such as the European Committee of the Regions and the European Monetary Institute (European Central Bank since 1998), and the granting of greater powers to pre-existing institutions, such as the European Parliament, the Court of Justice of the European Union, the European Court of Auditors, and the European Economic and Social Committee.
  • The strengthening of the Common Foreign and Security Policy (CFSP) to act jointly in foreign policy matters.
  • Police and judicial cooperation between the governments of the Member States, initiated with the Justice and Home Affairs (JHA) and the subsequent creation of Europol (European police agency).

The "Europe of the Fifteen" and the Treaty of Amsterdam

Despite the changes occurring in Europe in the late 1980s and early 1990s, the European Community (European Union since 1993) continued to receive membership applications.

Negotiations with Austria, Sweden, Finland and Norway began in 1993, which were straightforward due to the high economic development of these countries. Ratification of the accession treaties took place in 1994, with the exception of Norway (where a referendum decided against membership).

Accession came into force on January 1, 1995, giving rise to the "Europe of the Fifteen".

At the beginning of 1996, an Intergovernmental Conference (IGC) was convened to draft a new treaty that would amend the Maastricht Treaty.

The objectives of the new treaty were to develop the "Europe of the citizens", promote the role of the European Union in international politics, reform European institutions, and address an enlargement to the aspiring countries of Central and Eastern Europe.

After a long negotiation, a consensus was reached at the European Council held in Amsterdam on June 16 and 17, 1997. Thus was born the Treaty of Amsterdam, which came into force on May 1, 1999.

The fifth enlargement of the European Union

Following the fall of communist regimes in Central and Eastern Europe in 1989, the countries in the region viewed accession to the European Economic Community (European Union since 1993) as the best means to address their economic, political, and security issues. For the European Union, incorporating new members was an opportunity to increase its international influence.

The countries in Central and Eastern Europe, as well as Cyprus, Malta, and Turkey (which had also applied for membership), had very dissimilar economic and political situations, posing a political challenge for the European Union, which had to agree on institutional reforms.

The Copenhagen European Council (1993) recognized the legitimate aspirations of these countries and agreed on accession criteria to be met by applicants, membership requiring:

  • The existence of stable institutions guaranteeing democracy, the rule of law, respect for and protection of minorities.
  • A functioning market economy and the capacity to cope with market forces within the European Union.
  • Abiding by the obligations of membership and, in particular, subscribing to the objectives of political, economic and monetary union.

In 1997, the European Commission published Agenda 2000, entitled "For a stronger and wider Europe", in which it presented its decisions on the membership applications of Cyprus and the countries of Central and Eastern Europe, and established a financial aid program. The following year, accession negotiations began.

In December 2000, a summit was held in Nice, France, where the Charter of Fundamental Rights of the European Union was proclaimed, and the institutional reform of the European Union was agreed upon (embodied in the Treaty of Nice, signed in February 2001). The aim was to ensure the effectiveness of the EU in light of the imminent inclusion of ten new member countries.

The enlargement of the European Union took place on May 1, 2004, when Cyprus, Malta, the Czech Republic, Poland, Slovakia, Slovenia, Estonia, Latvia, Lithuania, and Hungary joined. In 2007, Bulgaria and Romania also became members, followed by Croatia in 2013.

Previously, on January 1, 1999, the euro had been adopted as the official currency of most EU countries (although euro banknotes and coins began to circulate in January 2002), and several of the new member states gradually started to adopt the euro. Today, twenty countries have the euro as their official currency.

From the Lisbon Treaty to Brexit

In 2020, the United Kingdom withdrew the European Union following a referendum.

A few months after the signing of the Treaty of Nice, the terrorist attacks of September 11, 2001 took place in the United States. These events prompted the Laeken Declaration, in which the European Council announced the strengthening of security and defense policy, and the fight against terrorism.

In 2004, the signing of a new treaty that would establish a European Constitution was agreed. This treaty was signed in Rome in October 2004, but was rejected by two referendums held in France and the Netherlands and, ultimately, it was not ratified.

Nevertheless, the majority of the provisions of the European Constitution were incorporated in a new treaty which today forms the constitutional basis of the European Union: the Lisbon Treaty (signed in 2007 and in force since December 1, 2009). This treaty amended and simplified previous treaties. Its main provisions include:

  • Granting the European Union legal status to sign international agreements as a community.
  • Making the Charter of Fundamental Rights binding for all member states.
  • Recognizing European citizenship for all nationals of member countries.
  • Increasing the number of Members of the European Parliament (MEPs), and granting more power to the European Parliament (in addition to other institutional reforms).

In 2012, the European Union was awarded the Nobel Peace Prize. Nevertheless, one of the most significant events in recent years was the United Kingdom's withdrawal from the European Union (a process known as Brexit) on January 31, 2020, following a referendum held in that country in June 2016.

Explore next:


  • Fernández Navarrete, D. (2022). History of the European Union: From Origins to Post-Brexit. Autonomous University of Madrid Publications.
  • Gabel, M. J. (2022). European Union. Encyclopedia Britannica. https://www.britannica.com/
  • European Union (n.d.). Principles, countries, history. Official European Union Portal. https://european-union.europa.eu/
  • University of Valencia (n.d.). Open Europa. Educational resources about the European Union. https://www.openeuropeuv.es/

How to cite

Citing the original source of information serves to duly credit authors and avoid plagiarism. Furthermore, it allows readers to have access to the original sources used in a text to verify or expand on information if necessary.

To cite properly, we recommend doing so according to APA standards, which are international standard guidelines followed by leading academic and research institutions worldwide.

GAYUBAS, Augusto. "History of the European Union".
Encyclopedia of Humanities. 22 January, 2024, https://humanidades.com/en/history-of-the-european-union/.

About the author

Author: Augusto Gayubas

PhD in history (University of Buenos Aires)

Translated by: Marilina Gary

Degree in English Language Teaching (Juan XXIII Institute of Higher Education, Bahía Blanca, Argentina).

Updated on: 22 January, 2024
Posted on: 28 September, 2023

Was this information useful to you?


    Thank you for visiting us :)