In 1919 British and American delegates to the Paris Peace Conference, under the leadership of Lionel Curtis, conceived the idea of an Anglo-American Institute of foreign affairs to study international problems with a view to preventing future wars. In the event, the British Institute of International Affairs was founded separately in London in July 1920. The American delegates developed the Council on Foreign Relations in New York as a sister institute. 

In 1923, the Institute acquired, through the gift of Colonel RW Leonard, Chatham House, Number 10 St. James's Square. The listed building was home to three prime ministers (William Pitt the Elder, Edward Stanley and William Gladstone).

In 1926, the Institute received its Royal Charter, thereupon being known as the Royal Institute of International Affairs. The Charter set out the aims and objectives of the Institute, reaffirming its wish to 'advance the sciences of international politics...promote the study and investigation of international questions by means of lectures and discussion…promote the exchange of information, knowledge and thought on international affairs'.

1929 marked the inception of the Institute's special study group on the international gold problem. The group, which included leading economists such as John Maynard Keynes, conducted a three year study into the developing economic issues which the post-war international monetary settlement created. The group’s research anticipated Britain’s decision to abandon the gold standard two years later.

Around this time Chatham House became known as the place for leading statesmen and actors in world affairs to visit when in London; notably, Mahatma Gandhi visited the institute on 20 October 1931, in which he delivered a talk on ‘The Future of India’. 

In 1933, Chatham House also held the first in a series of unofficial Commonwealth Relations Conferences to consider the challenges facing the increasingly independent members of the Commonwealth.

In 1937, Robert Cecil was also awarded the Nobel Prize for his commitment to, and defence of, the League of Nations and the pursuit for peace and disarmament amongst its members.

War years, 1939-45

The outbreak of WWII led the chairman, Lord Astor, to decentralize the Institute, with the majority of staff moving to Balliol College, Oxford. Throughout the war years the Institute worked closely with the Foreign Office who requested various reports on foreign press, historical and political background of the enemy and various other topics.

The Institute also provided many additional services to scholars and the armed forces. Research facilities were opened to refugee and allied academics, whilst arrangements were made for both the National Institute of Economic and Social Research and the Polish Research Centre to relocate to the Institute following the bombing of their premises. In addition, allied officers undertook courses in international affairs at the Institute in an attempt to develop their international and political awareness.

Post-war reconstruction

Chatham House had been researching potential post-war issues as early as 1939 through the Committee on Reconstruction. While a number of staff returned to the Institute at the end of the war, a proportion of members found themselves joining a range of international organizations, including the United Nations and the International Monetary Fund.

In reaction to the changing post-war world, Chatham House embarked on a number of studies relating to Britain and the Commonwealth’s new political stature and the development of the Cold War. The Institute held a series of conference on European questions and Western defence in cooperation with the Centre d’études de politiques étrangeres and the Deutsche Gesellschaft für Auswärtige Politik. Following the Cuban missile crisis and Brazilian coup d'état, the Institute also developed a growing focus on the Latin American region.

1970s and 1980s

A study group on ‘Europe since 1972’ was set up as part of a wider examination of the benefits and implications of the enlargement of the European Economic Community (EEC), including Britain’s accession in 1973. 

In October 1975 the first Anglo-Soviet round-table was held, beginning a series of meetings between Chatham House and the Institute of World Economy and International Relations in Moscow. As an early example of two-track diplomacy, the meeting sought to develop closer communication and improved relations between Britain and the Soviet Union, one of the first such attempts in the Cold War.

At the start of the 1980s, the Council moved to expand the Institute's research capabilities in two key emerging areas. The first modern programmes to be created under this initiative were the Energy and Research Programme and the International Economics Programme, formed in 1981.

In addition to reshaping its research practices, the Institute also sought to strengthen its international network, notably among economically prosperous nations. For example, Chatham House’s Far East programme was bolstered by the support of the Japan 2000 group in 1984.

Recent history

The Institute celebrated its 75th anniversary in 1995, an event marked by the visit of HM The Queen and the Duke of Edinburgh. During her visit, the Queen was briefed by the Institute’s experts on South Africa in preparation for her impending visit to the country following the end of apartheid.

The Chatham House Prize was launched in 2005, recognizing individuals who made a significant contribution to international relations in the previous year. HM The Queen presented the debut award to Ukrainian President Victor Yushchenko.

In 2009, Chatham House was named the top Non-US think tank by the University of Pennsylvania’s Global Go To Think Tanks survey, a position it has held for the past six years.

In January 2013 the Institute announced its Academy for Leadership in International Affairs, offering potential and established world leaders a 12 month fellowship at the institution with the aim of providing ‘a unique programme of activities and training to develop a new generation of leaders in international affairs.’ Chatham House also negotiated a 999-year lease on the ground floor of the adjacent building, Ames House, with further options to expand and accommodate the Institute’s planned growth. In November 2014, the Academy was formally launched by HM The Queen and renamed the Queen Elizabeth II Academy for Leadership in International Affairs in her honour.