Which treaty created the European Economic Community in 1957?

The Treaty of Rome created the European Economic Community in 1957.

Signed on 25 March 1957, the treaty was formally the Treaty Establishing the European Economic Community. The same ceremony also produced the Euratom Treaty, which established cooperation in atomic energy. Belgium, France, Italy, Luxembourg, the Netherlands, and West Germany were the six signatory states.

The European Economic Community aimed to build a common market and gradually remove barriers to trade among its members. It established institutions and policies that helped shape later European integration, including the customs union and common agricultural policy.

The treaty entered into force on 1 January 1958. The European Economic Community later became part of the European Union through the Maastricht Treaty, which entered into force in 1993. The Treaty of Paris is associated with the earlier European Coal and Steel Community, so it is a related but different milestone.