Were the benelux countries the start of the European Union?

In 1957 Belgium, Netherlands and Luxembourg were 3 of the 6 founding members of the European Economic Community, which is now known as the European Union. The other 3 founder members were Germany, France and Italy.
In 1957 Belgium, Netherlands and Luxembourg were 3 of the 6 founding members of the European Economic Community, which is now known as the European Union. The other 3 founder members were Germany, France and Italy.