In a process that began with the Maastricht Treaty of 1991 and concluded on January 1, 1999, 11 Western European countries made the euro the European Union's single currency, and the European Central Bank (ECB) the EU's only policymaking central bank. Bringing together Germany, France, Italy, and other European countries into a monetary union with a single currency and a single monetary policy could only ever result in major imbalances between the member countries, thus threatening the EU itself. This was recognized from the start by many economists and other observers, and the political elite paid elaborate lip service to these warnings.
