European Monetary System (EMS) was an arrangement established in 1979 under the Jenkins European Commission where most nations of the European Economic Community (EEC) linked their currencies to prevent large fluctuations relative to one another.
After the demise of the Bretton Woods system in 1971, most of the EEC countries agreed in 1972 to maintain stable exchange rates by preventing exchange rate fluctuations of more than 2.25% (the European "currency snake"). In March 1979, this system was replaced by the European Monetary System, and the European Currency Unit (ECU) was defined.
The basic elements of the arrangement were:
Although no currency was designated as an anchor, the Deutsche Mark and German Bundesbank soon emerged as the centre of the EMS. Because of its relative strength, and the low-inflation policies of the bank, all other currencies were forced to follow its lead if they wanted to stay inside the system. Eventually, this situation led to dissatisfaction in most countries, and was one of the primary forces behind the drive to a monetary union (ultimately the euro).
Periodic adjustments raised the values of strong currencies and lowered those of weaker ones, but after 1986 changes in national interest rates were used to keep the currencies within a narrow range. In the early 1990s the European Monetary System was strained by the differing economic policies and conditions of its members, especially the newly reunified Germany, and Britain (which had initially declined to join and only did so in 1990) permanently withdrew from the system in September 1992. Speculative attacks on the French Franc during the following year led to the so-called Brussels Compromise in August 1993 which established a new fluctuation band of +15%.
European currency exchange rate stability has been one of the most important objectives of European policy makers at least since the Second World War.