Although the term "multilateralism" started to be used in political arenas after the Second World War, the idea of organizing the international system to maintain peace is very old. Here, you can discover the origins of today’s international system at different levels: intellectual, political, technical, and institutional. This exploration shows the milestones and highlights the continuities as well as the ruptures that marked the history of multilateralism.

Participants to one of the International Peace Congresses held during the second half of the 19th century.

The Origins of Multilateralism

The intellectual reflection on how to organize the international system to establish lasting peace has a long history.

Käthe Kollwitz, Die Mütter (

The Genesis of the League of Nations

The First World War was the catalyst for the creation of the League of Nations, the first global international organization established to maintain peace and promote international cooperation.

Haile Selassie, Emperor of Ethiopia at the rostrum of the Assembly.

The League of Nations

Find out why the League of Nations was more than a mere failure, as it has long been characterized, and to what extent the League’s “great experiment" marked a significant evolution in multilateralism.

Propaganda poster of the United Nations.

The United Nations

How was the United Nations established? Discover the milestones of its creation.