The ILO was created in 1919, as part of the Treaty of Versailles that ended World War I, to reflect the belief that universal and lasting peace can be accomplished only if it is based on social justice.

The Constitution was drafted between January and April, 1919, by the Labour Commission set up by the Peace Conference, which first met in Paris and then in Versailles. The Commission, chaired by Samuel Gompers, head of the American Federation of Labour (AFL) in the United States, was composed of representatives from nine countries: Belgium, Cuba, Czechoslovakia, France, Italy, Japan, Poland, the United Kingdom and the United States. It resulted in a tripartite organization, the only one of its kind bringing together representatives of governments, employers and workers in its executive bodies.

The Constitution contained ideas tested within the International Association for Labour Legislation, founded in Basel in 1901. Advocacy for an international organization dealing with labour issues began in the nineteenth century, led by two industrialists, Robert Owen (1771-1853) of Wales and Daniel Legrand (1783-1859) of France.