Schuman Plan
The plan for a supra-national European Coal and Steel Community proposed by the French Foreign Minister, Robert Schuman on 9th May 1950. This day has become known as the birthday of the EU.
Future
The EU Constitution proposes that the day officially become "EU-day".
Links
Declaration of 9 May 1950: http://europa.eu/abc/symbols/9-may/decl_en.htm