In 1949, there were 12 founding members of the Alliance. Provision for enlargement is given by Article 10 of the North Atlantic Treaty, which states that membership is open to any “European State in a position to further the principles of this Treaty and to contribute to the security of the North Atlantic area”.
The founding members
On 4 April 1949, the foreign ministers from 12 countries signed the North Atlantic Treaty at the Departmental Auditorium in Washington D.C.: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom and the United States.
Within the following five months of the signing ceremony, the Treaty was ratified by the parliaments of the interested countries, sealing their membership.
The 12 signatories
Some of the foreign ministers who signed the Treaty were heavily involved in NATO’s work at a later stage in their careers:
- Belgium: M. Paul-Henri Spaak (NATO Secretary General, 1957-1961);
- Canada: Mr. Lester B. Pearson (negotiated the Treaty and was one of the “Three Wise Men” who drafted the report on non-military cooperation in NATO, published in 1956 in the wake of the Suez crisis);
- Denmark: Mr. Gustav Rasmussen;
- France: M. Robert Schuman (architect of the European institutions, who also initiated the idea of a European Defence Community);
- Iceland: Mr. Bjarni Benediktsson;
- Italy: Count Carlo Sforza;
- Luxembourg: M. Joseph Bech;
- the Netherlands: Dr. D.U. Stikker (NATO Secretary General, 1961-1964);
- Norway: Mr. Halvard M. Lange (one of the “Three Wise Men” who drafted the report on non-military cooperation in NATO);
- Portugal: Dr. Jose Caerio da Matta;
- the United Kingdom: Mr. Ernest Bevin (main drive behind the creation of NATO and as Foreign Secretary from 1945 to 1951, he attended the first formative meetings of the North Atlantic Council);
- the United States: Mr. Dean Acheson (as US Secretary of State from 1949 to 1953, he attended and chaired meetings of the North Atlantic Council).
Flexibility of NATO membership
On signing the Treaty, countries voluntarily commit themselves to participating in the political consultations and military activities of the Organization. Although each and every signatory to the North Atlantic Treaty is subject to the obligations of the Treaty, there remains a certain degree of flexibility which allows members to choose how they participate. The memberships of Iceland and France, for instance, illustrate this point.
When Iceland signed the Treaty in 1949, it did not have – and still does not have – armed forces. There is no legal impediment to forming them, but Iceland has chosen not to have any. However, Iceland has a Coast Guard, national police forces, an air defence system and a voluntary expeditionary peacekeeping force. Since 1951, Iceland also benefits from a long-standing bilateral defence agreement with the United States. In 2006, US forces were withdrawn but the defence agreement remains valid. Since 2008, air policing has been conducted on a periodic basis by NATO Allies.
Today, Iceland with its population of 320 000 is represented on all of NATO’s principal committees; it pays toward NATO’s military budget, civilian budget and the NATO Security and Investment Programme. Since 2006, it has also assumed the responsibility of a host and user nation to NATO infrastructure based in Iceland. Iceland also contributes civilian peacekeepers to NATO-led operations. It regularly hosts NATO exercises and events, and is taking a more active role in NATO deliberations and planning.
In 1966, President Charles De Gaulle decided to withdraw France from NATO’s integrated military structure. This reflected the desire for greater military independence, particularly vis-à-vis the United States, and the refusal to integrate France’s nuclear deterrent or accept any form of control over its armed forces.
In practical terms, while France still fully participated in the political instances of the Organization, it was no longer represented on certain committees, for instance, the Defence Planning Committee and the Nuclear Planning Group. This decision also led to the removal of French forces from NATO commands and foreign forces from French territory. The stationing of foreign weapons, including nuclear weapons, was also banned. NATO’s political headquarters (based in Paris since 1952), as well as the Supreme Headquarters Allied Powers Europe or SHAPE (in Rocquencourt since 1951) moved to Belgium.
Despite France’s withdrawal from NATO’s integrated military structure, two technical agreements were signed with the Alliance, setting out procedures in the event of soviet aggression. Since the fall of the Berlin Wall, France has regularly contributed troops to NATO’s military operations, making it one of the largest troop-contributing states. It is also NATO’s fourth biggest contributor to the military budget.
From the early 1990s onwards, France distanced itself from the 1966 decision with, for instance, its participation at the meetings of defence ministers from 1994 (Seville) onwards and the presence of French officers in ACO and ACT structures from 2003. At NATO’s Strasbourg/Kehl Summit, April 2009, France officially announced its decision to fully participate in NATO structures¹.
The accession of Greece and Turkey
Three years after the signing of the Washington Treaty, on 18 February 1952, Greece and Turkey joined NATO. This enabled NATO to reinforce its “southern flank”.
At a time when there was a fear of communist expansion throughout Europe and other parts of the world (soviet support of the North Korean invasion of South Korea in 1950), extending security to south-eastern Europe was strategically important. Not only did NATO membership curb communist influence in Greece – a country recovering from civil war - but it also relieved Turkey from soviet pressure for access to key strategic maritime routes.
The accession of Germany
Germany became a NATO member on 6 May 1955. This was the result of several years of deliberations among western leaders and Germany, whose population opposed any form of rearmament.
Following the end of the Second World War, ways of integrating Germany into West European defence structures was a priority. When the European Defence Community failed, Germany joined the Western Union, which became the Western European Union as soon as it had adhered to the organization. This, together with the termination of its status as an occupied country, was a stepping stone to becoming a member of NATO.
The Federal Republic of Germany officially joined the Western Union on 23 October 1954 and its status as an occupied country came to an end when the Bonn-Paris conventions came into effect on 5 May 1955. The next day, it became NATO’s 15th member country.
With the reunification of Germany on 3 October 1990, the länders of the former German Democratic Republic joined the Federal Republic of Germany in its membership of NATO.
The accession of Spain
Despite considerable public opposition, Spain joined the Alliance on 30 May 1982, but refrained from participating in the integrated military structure. This position was reaffirmed in a referendum held in 1986.
Spain fully participated in the political instances of the Organization. With regard to the military aspects, it was present as an observer on the Nuclear Planning Group; reserved its position on participation in the integrated communication system; maintained Spanish forces under Spanish command and did not accept to have troops deployed outside of Spain for long periods of time. Nevertheless, Spanish forces would still be able to operate with other NATO forces in an emergency.
Spain’s reservations gradually diminished and at the nomination of Dr Javier Solana as NATO’s first Spanish Secretary General (1995-1999), the Spanish Parliament endorsed the country’s participation in the integrated military command structure (1996).
The first wave of post-Cold War enlargement
The fall of the Berlin Wall and the dissolution of the Warsaw Pact after the end of the Cold War opened up the possibility of further NATO enlargement. Some of the new democracies of Central and Eastern Europe were eager to become integrated into Euro-Atlantic institutions.
In 1995, the Alliance carried out and published the results of a Study on NATO Enlargement that considered the merits of admitting new members and how they should be brought in. It concluded that the end of the Cold War provided a unique opportunity to build improved security in the entire Euro-Atlantic area and that NATO enlargement would contribute to enhanced stability and security for all.
The Czech Republic, Hungary and Poland were invited to begin accession talks at the Alliance’s Madrid Summit in 1997 and on 12 March 1999 they became the first former members of the Warsaw Pact to join NATO.
Drawing heavily on the experience gained during this accession process, NATO launched the Membership Action Plan - or MAP - at the Washington Summit in April 1999. The MAP was established to help countries aspiring to NATO membership in their preparations, even if it did not pre-judge any decisions.
The second wave of post-Cold War enlargement
Bulgaria, Estonia, Latvia, Lithuania, Romania and Slovakia and Slovenia were invited to begin accession talks at the Alliance’s Prague Summit in 2002. On 29 March 2004, they officially became members of the Alliance, making this the largest wave of enlargement in NATO history.
All seven countries had participated in the MAP before acceding to NATO.
The accession of Albania and Croatia
The most recent accessions are those of Albania and Croatia. Albania had participated in MAP since its inception in 1999 and Croatia joined in 2002. They worked with NATO in a wide range of areas, with particular emphasis on defence and security sector reform, as well as support for wider democratic and institutional reform.
In July 2008, they both signed Accession Protocols and became official members of the Alliance on 1 April 2009.
1. However, France has chosen not to become a member of NATO's Nuclear Planning Group.