Only five years after the end of the Second World War, mistrust was still reigning between the peoples of Europe. How could France and Germany be reconciled in the long term? The Declaration of 9 May 1950 was to be the ambitious project that would change the destiny of Europe by laying the foundations of the European Coal and Steel Community (ECSC), which would later become the European Union. A race against time was taking place against the backdrop of the Cold War and the great dangers to peace.