When Marquis Masson de Pezay voiced the hope in 1771 that a Society of Nations might be established in Switzerland, he was merely trying to cheer up his listeners who were complaining about living in a land of mountains, rocks and lakes. That wish came true on 16 January 1920, when the League of Nations was inaugurated. Its secretariat was based in Geneva and in 1936, it moved to the newly built Palais des Nations.
The architectural competition had been launched with the following intention:
- « The Palais, whose construction is the object of the competition, is intended to house all the organs of the League of Nations in Geneva. It should be designed in such a way as to allow these organs to work, to preside and to hold discussions, independently and easily in the calm atmosphere which should prevail when dealing with problems of an international dimension. »
After the dissolution of the League of Nations in 1946 and the transfer of its assets to the United Nations Organization, the European Office of the United Nations was established in the Palais des Nations, becoming the United Nations Office at Geneva in 1966.
The Palais stands in the 45-hectare Ariana Park among majestic trees many of which are over 100 years old. The City of Geneva has made the park available to the UN for its offices for as long as the UN exists. The park was originally owned by the Revilliod de Rive family whose last descendant bequeathed it to the City of Geneva. One of the bequest's conditions was that peacocks should roam freely on its grounds. It is not unusual to see peacocks dancing in full splendor in the Palais grounds. The park also contains a 1668 chalet brought from the Gruyere district to Geneva for the national fair of 1896.
Beneath the foundation stone of the Palais des Nations laid on 7 September 1929 lies a casket containing a document listing the names of the League of Nations Member States, a copy of the Covenant of the League and specimen coins of all the countries represented at its Tenth Assembly.