Multinational Defence Cooperation (MDC) is part of the everyday life of European armed forces. It has become such a natural and self-evident phenomenon for European military personnel and policymakers that they do not even think about its causes any more although it shapes almost every aspect of defence. MDCs have a massive effect on the defence policies, force structures, capability development plans and defence industrial considerations of individual European states. This is reflected in the strategic documents of European countries and the fact that they do not go to war without the support of other European states. Furthermore, most of the sophisticated weapon systems developed by European countries have been multinational projects for decades, and they cost billions or tens of billions of Euros. Every year tens of thousands of European troops participate in multinational military exercises, dozens of multinational units have been created for the last thirty years and Europeans also procure and maintain military capabilities together.

However, this level of cooperation did not happen overnight; rather, it has been the result of a decades-long evolution of collaborations. This chapter defines what an MDC is in the context of the book and also defines what the concepts of region and subregion are, pointing out the relevance of the subregional dimension of MDCs. The second half of the chapter outlines the broader history of defence collaborations in Europe between 1990 and 2010, as the studied three case studies were established in the late 2000s and early 2010s.

Multinational defence cooperation in Europe and the subregional dimension

The UK Ministry of Defence defines ‘Multinational Defence Cooperation (MDC) as any arrangement where two or more nations work together to enhance military capability. This can include exchanges and liaison, training and exercising, common doctrine, collaborative equipment procurement, or multinational formations’ (UK Ministry of Defence, 2001: 2). The book uses this definition as a basis to inform its research, but it will amend it slightly as it acknowledges that this definition might seem too broad for analytical purposes. For instance, one might question the usefulness of a definition that covers everything from the exchange of liaison officers between two countries to collaborative equipment procurement including several countries.