The Treaty of Rome established the European Economic Community in 1957.
Signed on 25 March 1957, the treaty formally created the European Economic Community, or EEC, and the European Atomic Energy Community. The six founding countries were Belgium, France, Italy, Luxembourg, the Netherlands, and West Germany. The agreement aimed to build a common market and encourage economic integration after the Second World War.
The EEC gradually removed trade barriers among its members and developed shared institutions. It later became part of the European Communities, which were incorporated into the European Union through the Maastricht Treaty in 1993. The Treaty of Rome is therefore a foundation of European integration, but it did not itself create the modern European Union.
The treaty should not be confused with the 1951 Treaty of Paris, which created the European Coal and Steel Community, an earlier step toward cooperation.