For centuries, Europe was the scene of frequent and bloody wars. In the period 1870 to 1945, France and Germany fought each other three times, with terrible loss of life. A number of European leaders became convinced that the only way to secure a lasting peace between their countries was to unite them economically and politically.
So, in 1950, the French Foreign Minister Robert Schuman proposed integrating the coal and steel industries of Western Europe. As a result, in 1951, the European Coal and Steel Community (ECSC) was set up, with six members: Belgium, West Germany, Luxembourg, France, Italy and the Netherlands. The power to take decisions about the coal and steel industry in these countries was placed in the hands of an independent, supranational body called the "High Authority". Jean Monnet was its first President.
The ECSC was such a success that, within a few years, these same six countries decided to go further and integrate other sectors of their economies. In 1957 they signed the Treaties of Rome, creating the European Atomic Energy Community (EURATOM) and the European Economic Community (EEC). The member states set about removing trade barriers between them and forming a "common market".
In 1967 the institutions of the three European communities were merged. From this point on, there was a single Commission and a single Council of Ministers as well as the European Parliament.
The Treaty of Maastricht (1992) introduced new forms of co-operation between the member state governments - for example on defence, and in the area of "justice and home affairs". By adding this inter-governmental co-operation to the existing "Community" system, the Maastricht Treaty created the European Union (EU).
It took some time for the Member States to remove all the barriers to trade between them and to turn their "common market" into a genuine single market in which goods, services, people and capital could move around freely.