Western European Union

Structure and membership

The WEU began with five Western European signatories of the original treaty. In 1954 the organisation was reshaped by agreements that allowed additional states to join; notably West Germany and Italy became members, and the body became commonly known as the Western European Union. Its institutional layout included a council of foreign and defence ministers, an international staff and a parliamentary assembly composed of national parliamentarians who met to examine security and defence matters.

Roles and functions

During the Cold War the WEU served as a European forum complementary to transatlantic arrangements, facilitating cooperation on collective defence and the coordination of military preparations. In the 1990s it developed a set of priorities—often summarized as crisis management, humanitarian tasks and peacekeeping—that influenced later European policy. Known as the Petersberg tasks, these concepts were subsequently taken up by the European Union's security and defence initiatives.

History and transition

After the end of the Cold War, the landscape of European security changed and many of the WEU's responsibilities and programmes were progressively transferred to other institutions. The European Union expanded its role in security and defence policy, incorporating the Petersberg tasks into its framework, while other aspects of European cooperation moved into multilateral bodies including the Council of Europe (Council of Europe). The WEU continued in a reduced capacity until it was formally dissolved on 31 March 2011.

Legacy and significance

The WEU is remembered for helping to bridge national defence concerns and for shaping early debates on European crisis management. It provided a stepping stone between postwar bilateral arrangements and the development of a common European approach to security. Its institutional lessons and policy concepts remain part of the wider European security architecture, even though the organisation itself no longer exists.

• Founding treaty: Treaty of Brussels (1948).
• Key enlargement: accession of West Germany and Italy (1954).
• Headquarters: Brussels.
• Functions later taken on by the EU and other bodies, including the Council of Europe.