Estonia was the smallest continental European country that joined the EU during the major enlargement round in 2004 (with only the island of Cyprus being smaller).
Containing Germany has been the European project’s main raison d'être since its creation. This was symbolised by the fact that cooperation started with the European Coal and Steel Community (ECSC) in 1950, primarily aimed at avoiding another European war.
Austria joined the EU only in 1995, having traditionally been a neutral country, but has been part of the eurozone (1999) and Schengen (1997) areas since their inception.