On 9 May 1948, during the plenary session of the Cultural Committee of the Congress of Europe in The Hague, the Swiss philosopher and critic, Denis de Rougemont, rapporteur for the Committee, emphasises the importance of the cultural dimension of European unification.

On 22 April 1948, Denis de Rougemont gives a lecture at the Sorbonne on the cultural implications of European unity. He refers, in particular, to the opposition between the unionist and federalist tendencies within the pro-European activist movement.

On 29 March 1948, Joseph Retinger, Secretary-General of the International Committee of the Movements for European Unity, sends to Denis de Rougemont, who has been appointed rapporteur for the Cultural Committee at the forthcoming Congress of Europe, a letter in which he defines the nature and scope of the preamble to the Hague Declarations. This will become known as the ‘Message to Europeans’.

In May 1968, on the 30th anniversary of the Congress of Europe held in The Hague, Denis de Rougement outlines to the monthly publication Communauté Européenne his memories of the preparations for and the proceedings at this militant event which he attended in his capacity as rapporteur for the Cultural Affairs Committee.

In preparation for the European Conference on Culture held in Lausanne from 8 to 12 December 1949, the Planning Board for a European Centre for Culture led by the Swiss federalist, Denis de Rougemont, finalises a general report based on around 40 specialist reports which identifies the difficulties facing culture in Europe and proposes the establishment of a series of specifically European institutions responsible for its development.

On 16 December 1949, reporting in the French daily newspaper Le Monde on the European Conference on Culture that has recently come to an end in Lausanne, the French literary historian and essayist, Pierre-Henri Simon, comments on the exchange of letters between the Swiss author, Denis de Rougement, and the Romanian writer, Virgil Gheorghiu, on the subject of whether there is still a way of saving the old Europe.

During the final session of the Congress of Europe held in The Hague in May 1948, some 800 participants adopt the basic text, Message to Europeans, drawn up by the Swiss federalist, Denis de Rougemont.