Estonia was a member of the League of Nations from 22 September 1921, and became a member of the United Nations on 17 September 1991. Since restoration of independence Estonia has pursued close relations with the Western countries, and has been member of NATO since 29 March 2004, as well as the European Union since 1 May 2004. In 2007, Estonia joined the Schengen Area, and in 2011 the Eurozone. The European Union Agency for large-scale IT systems is based in Tallinn, which started operations at the end of 2012. Estonia held the Presidency of the Council of the European Union in the second half of 2017.
Since the early 1990s, Estonia has been involved in active trilateral Baltic states co-operation with Latvia and Lithuania, and Nordic-Baltic co-operation with the Nordic countries. The Baltic Council is the joint forum of the interparliamentary Baltic Assembly and the intergovernmental Baltic Council of Ministers. Estonia has built close relationship with the Nordic countries, especially Finland and Sweden, and is a member of Nordic-Baltic Eight (NB-8) uniting Nordic and Baltic countries. Joint Nordic-Baltic projects include the education programme Nordplus and mobility programmes for business and industry and for public administration. The Nordic Council of Ministers has an office in Tallinn with a subsidiaries in Tartu and Narva. The Baltic states are members of Nordic Investment Bank, European Union’s Nordic Battle Group, and in 2011 were invited to co-operate with NORDEFCO in selected activities.
The beginning of the attempt to redefine Estonia as “Nordic” was seen in December 1999, when then Estonian foreign minister (and President of Estonia from 2006 until 2016) Toomas Hendrik Ilves delivered a speech entitled “Estonia as a Nordic Country” to the Swedish Institute for International Affairs, with potential political calculation behind it being wish to distinguish Estonia from more slowly progressing southern neighbours, which could have postponed early participation in European Union enlargement for Estonia too. Andres Kasekamp argued in 2005, that relevance of identity discussions in Baltic states decreased with their entrance into EU and NATO together, but predicted, that in the future, attractiveness of Nordic identity in Baltic states will grow and eventually, five Nordic states plus three Baltic states will become a single unit.
Other Estonian international organisation memberships include OECD, OSCE, WTO, IMF, the Council of the Baltic Sea States, and on 7 June 2019, was elected a non-permanent member of the United Nations Security Council for a term that begins on 1 January 2020.
Relations with Russia remain generally cold, though there is some practical co-operation.