EU history begins with the formation of the Council of Europe in 1949.
The Fathers of Europe, also called “the 6 pioneers of Europe”, lay the foundations of the Council of Europe to defend a new set of European values such as human rights, the rule of law, and democracy.
In 1950 they initiate the European Coal and Steel Community and in 1957 they establish the European Economic Community.

European Coal and Steel Community (ECSC)
As the aid from the Marshall Plan stopped coming to Europe in 1949, in 1950 the Minister of Foreign Affairs of France, Robert Shuman came up with the proposal to initiate the Shuman Plan, which represents a proposal to form a European organization to manage the production of coal and steel in the Ruhr Basin. In 1951, following the Treaty of Paris, the states with interests in the Ruhr Basin sign the Treaty, which in article 100 stipulates that the signatory states form an organization for the efficient management of coal and steel resources (CEEC).
The signatory states (France, West Germany, Italy, Belgium, Luxembourg, and the Netherlands) agreed that this international organization aimed to establish a common market for coal and steel with the aim of increasing the economy, the standard of living, to rationalize the distribution of production and to guarantee jobs.
This community was the first step of the European states towards a close international collaboration.
The European Economic Community (EEC) and the European Atomic Energy Community (Euratom)
In 1957 in Rome, the Europeans sign the Treaties that lay the foundations of other two European Communities, namely the European Economic Community (EEC) and the European Atomic Energy Community (Euratom). If the CEEC was a community based on international law and international cooperation, then the EEC and Euratom were slightly different communities. They brought a different model of European collaboration, which is why the national states reacted immediately stipulating the national sovereignty argument. From here can be easily seen the nationalist Europe that was, and still is, quite sensitive to changes formulated at the international level.
The main goal of the European Economic Community was to create a free trade area with a common external tariff. This was meant to encourage economic development and to gradually develop political collaboration and integration. The first change in this direction is to be observed in 1962 when common prices for agricultural products were established and the foundations of the Common Agricultural Policy were laid. Then, in 1968, most of the internal tariffs were removed and trade between nations moved to another level.
On the other hand, Euratom had the purpose of organizing, managing, and promoting the cooperation of the European states in the field of nuclear energy.
Until now, Europe has 3 organizations, each with its institutions. But, a major change was to happen in 1965, which brought the European states even closer.
The merger treaty
The above-mentioned European organizations had an institutional structure that allowed them to function as such. Yet, given that all pursued this general goal: the social well-being and economic development of all member states, and because the CEE gradually took over the functions and fulfilled the objectives of the other organizations in 1965, at the Brussels treaty, the merger of the executives is signed. From this moment on, the 3 organizations have the same Commission and Council. The treaty unifies similar institutions by establishing a single Council and a Single Commission for all organizations, while the other institutions remain separate and continue to perform different functions.

The Single European Act
In 1985, the 3 European organizations decided to take the cooperation to another level. So, they establish a framework for political cooperation. The Single European Act brings a major change at the level of institutions, namely what was previously called the Common Assembly since the entry into force of the Single European Act is called the European Parliament. Also, the act endows the Parliament with a set of legislative powers by introducing cooperation and approval procedures.
At the same time, the Commission gains some executive powers. According to Article 10 of the Treaty, the Council can give to the Commission the right to execute the rules adopted by the Council. However, the Council could reserve this right for special situations.
In addition to this, the AEU establishes the European Council, formalizing the meetings at the level of heads of state or government, which only officially becomes an EU institution with the Treaty of Lisbon.
Also, the Act relaunches the idea of European integration and brings back into discussion the need for an internal market.
The Maastricht Treaty and the EU
In 1988, the European states discussed the need to form an Economic Monetary Union (EMU) to facilitate economic transactions on the territory of Europe. In this sense, the Maastricht Treaty comes as a necessary step for the realization of an internal market, the EMU, but also a Europe of political cooperation.
As a result, in 1992 the member states of the European Communities sign the Treaty of Maastricht, which brings the following new elements:
- the treaty revises the treaties based on which the European Communities were formed and introduced the name of the European Union (the member states agree on the need to change and reformulate European cooperation under another name and another form);
– laid the foundations for the three pillars of the EU: 1) European Communities; 2) Justice and Internal Affairs; 3) Common Foreign and Security Policy. The pillars were intended to create an effective union that can protect and fulfill the interests of its citizens. This helped the Union to be more effective, inclusive, transparent, and responsible. - established the foundations of the Economic and Monetary Union.

Treaty of Amsterdam
After the Maastricht Treaty, the Union went through various political and economic changes. The waves of enlargement started as early as 1973 with the accession of Great Britain, Ireland, and Denmark. But large waves of enlargement were ahead, and for this, the EU needed a well-established institutional organization. Following the enlargement plans and adhesion requests, in 1997 the Treaty of Amsterdam was signed which brought changes at the institutional level preparing the Union for new members. It increased the Union’s powers in relation to the member states and empowered the European Parliament even more so that it ended up having almost the same decision-making power in co-decision as the Council. The treaty also established the maximum number of parliamentarians, which can now be 700, taking into account the 1986 enlargement towards Spain and Portugal, and that from 1995 towards Austria, Finland, and Sweden.
The Treaty of Nice
In 2001, the Union was preparing for the 2004 enlargement wave, which was to incorporate 10 states (Cyprus, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, and Slovenia). This enlargement was the largest in the EU history; it was the largest wave of expansion both in terms of number of countries as well as population. So, preparing for a huge change, in 2001 the European states signed a new treaty to institutionally and structurally prepare the Union for expansion. The Treaty brought changes at the level of institutions such as changes in the method by which the president and members of the European Council were elected (by qualified majority vote in the Council); the president of the Commission got more rights in the Commission; the percentage in the voting procedure was changed, preparing the Union for the new expansion (with the aim of increasing political representativeness), and the majority is defined at 62% of the EU population to guarantee representativeness. Also, the number of European parliamentarians increases to 732 members, intending to allow the representation of citizens from 27 states.

The Treaty of Lisbon
The Treaty of Lisbon was signed in 2007 and entered into force in 2009. It aimed to make the Union more democratic and more efficient; to transform it into a global actor. The main changes the Treaty brought were at the level of the European Parliament, transforming it into an actor with a decision-making power equal to that of the Council.
Another change was the modification of the voting procedure in the Council. Also, the Treaty brought in front of the European citizens the Citizens’ Initiative – a way by which the Union offered its citizens the opportunity to participate directly in the decision-making process by formulating and placing in the white paper of the Commission a legislative proposal.
The Treaty of Lisbon transforms the European Council into an EU institution and establishes the role of the High Representative of the EU in Foreign and Security Policy.
At the same time, the treaty made a clear difference between the powers of the EU and those of the national states, emphasizing 3 classes of competencies: exclusive (which give the full right of action), shared (which requires the Union, or the national states, to consult each other), of support (which gives EU the right to consult the national states in certain fields and take action if the states delegate the right of action to the EU).
The Treaty of Lisbon refreshed and reformulated the set of goals and values of the Union, as well as the human rights charter. These were later incorporated into national policies and can be found in the daily life of Europeans.
For more see “The new social reality of the Europeans: a constructivist view over Europeanization”.

Sources:
The European Council, 2023. Who we are. Available at: coe.int/en/web/about-us/who-we-are
European Union, 2923. Schuman declaration May 1950. Available at: european-union.europa.eu/principles-countries-history/history-eu/1945-59/schuman-declaration-may-1950_en
European Parliament, 2023. Tratatul de Fuziune. Available at: europarl.europa.eu/about-parliament/ro/in-the-past/the-parliament-and-the-treaties/merger-treaty
European Parliament, 2023. Actul Unic European (AUE). Available at: europarl.europa.eu/about-parliament/ro/in-the-past/the-parliament-and-the-treaties/single-european-act
The European Council, 2023. How Maastricht changed Europe. Available at: consilium.europa.eu/en/maastricht-treaty/
European Parliament, 2023. The Maastricht and Amsterdam Treaties. Available at: europarl.europa.eu/factsheets/en/sheet/3/the-maastricht-and-amsterdam-treaties
Eur-Lex, 2018. Treaty of Nice. Available at: eur-lex.europa.eu/legal-content/EN/LSU/?uri=uriserv%3AOJ.C_.2001.080.01.0001.01.ENG