The World Council of Churches in Process of Formation (WCC) entered the ecumenical scene on the eve of the Second World War. Soon, it emerged as the new flagship for the ecumenical work of the ecumenically involved Orthodox and Protestant churches. The architects of the WCC were also determined to incorporate international affairs into the scope of the new council as an area of central concern. This newcomer within the modern ecumenical movement induced the gradual dissolution of the World Alliance movement, which had been the first organisational expression of churches concern for international affairs, and especially for world peace.

American ecumenists pressed for the creation of the Commission of the Churches on International Affairs (CCIA) soon after the end of the Second World War. Their proposal for a new ecumenical body was adopted by the Provisional Committee of the WCC at its first post-war meeting. The aims and functions of the CCIA were further discussed by the International Conference of Church Leaders on the Problems of World Order. At this Conference, 60 church leaders, mostly from Britain, Western Europe and the US, gave the green light to the creation of the CCIA in August 1946.