English man and GM

Currently, there are three agreements that involve different degrees of integration within the European Union: EU membership, membership in the euro area and participation in the Schengen agreement. EU membership does not necessarily entail participation in the Schengen Agreement. Not all EU member states are part of the euro area. Examples of different degrees of integration:
The UK and Ireland signed the Schengen Agreement on a limited membership basis. The UK also did not consider it necessary to join the euro zone.
Denmark and Sweden also decided in referendums to keep their national currencies.
Norway, Iceland, Switzerland and Liechtenstein are not members of the EU, but are part of the Schengen area.

1986 - the third expansion of the EEC (Spain and Portugal joined).
1986 - Single European Act - the first significant change in the founding treaties of the EU.
1992 - Signing of the Maastricht Treaty establishing the European Union on the basis of the European Economic Community.
1995 - fourth expansion (accession of Austria, Finland and Sweden).
1999 - the introduction of a single European currency - the euro (in cash circulation since 2002).
2004 - the fifth expansion (accession of the Czech Republic, Hungary, Poland, Slovakia, Slovenia, Estonia, Latvia, Lithuania, Cyprus, Malta).
2007 - Signing of the Reform Treaty in Lisbon.
2007 - the second wave of the fifth expansion (the accession of Bulgaria and Romania). The 50th anniversary of the creation of the EEC is being celebrated.
2013 - sixth expansion (Croatia joined).
2020 - UK exit from the union
2022 - Assigning Ukraine the status of Candidate for EU Membership

1951 - Signing of the Paris Treaty establishing the European Coal and Steel Community.
1957 - signing of the Treaty of Rome establishing the European Economic Community and Euratom.
1965 - the signing of a merger agreement, which resulted in the creation of a single Council and a single Commission for the three European communities of the ECSC, the EEC and Euratom. Entered into force on July 1, 1967.
1973 - the first expansion of the EEC (Denmark, Ireland, Great Britain joined).
1978 - Creation of the European Monetary System.
1979 - The first pan-European elections to the European Parliament.
1981 - the second expansion of the EEC (Greece joined).
1985 - signing of the Schengen agreement.

In order to deepen economic integration, the same six states in 1957 established the European Economic Community (EEC, Common Market) (EEC - European Economic Community) and the European Atomic Energy Community (Euratom, Euratom - European Atomic Energy Community). The most important and broadest of these three European communities was the EEC.
The process of development and transformation of these European communities into the modern European Union took place through, firstly, the transfer of an increasing number of management functions to the supranational level and, secondly, an increase in the number of integration participants.
Sixties movement - period of economic growth (1960-1969)

The ideas of pan-Europeanism, long put forward by thinkers throughout the history of Europe, sounded with particular force after the Second World War. In the post-war period, a number of organizations appeared on the continent: the Council of Europe, NATO, the Western European Union.
Peaceful Europe - the beginning of unification (1945-1959)
The first step towards the creation of a modern European Union was taken in 1951: Belgium, West Germany [nb 4], the Netherlands, Luxembourg, France, Italy signed an agreement establishing the European Coal and Steel Community (ECSC, ECSC - European Coal and Steel Community), whose goal was to pool European resources for the production of steel and coal, this agreement entered into force in July 1952.

The number of countries participating in the union has grown from the initial six - Belgium, West Germany[nb 4], Italy, Luxembourg, the Netherlands and France - to today's 27 through successive expansions: by joining the treaties, countries have limited their sovereignty in exchange for representation in institutions union acting in the common interest[21].
To join the European Union, a candidate country must comply with the Copenhagen criteria, adopted in June 1993 at the meeting of the European Council in Copenhagen and approved in December 1995 at the meeting of the European Council in Madrid. The criteria require that the state observes democratic principles, the principles of freedom and respect for human rights, as well as the principle of the rule of law. Also, the country should have a competitive market economy, and should recognize the common rules and standards of the EU, including commitment to the goals of political, economic and monetary union[22].
Greenland, an autonomous territory of Denmark, withdrew from the European Communities in 1985. The Lisbon Treaty provides for the conditions and procedure for the withdrawal of any state from the union. This procedure was used by the United Kingdom, which withdrew from the Union on January 31, 2020[23].
Currently 5 countries have candidate status and are negotiating membership: