Warfare has shaped the history of the twentieth century. The Paris Peace Conference, held at the end of the First World War, proved to be a pivotal moment in the history of Europe. National boundaries were reshaped, and the continent was plunged into the political chaos of revolution, dictatorship and, ultimately, more war. This key event is represented by William Orpen's commissioned painting The Signing of the Peace in the Hall of Mirrors, Versailles, 28th June 1919 [ART 2856], which captures the leaders of the Allied countries in confident pose after months of complex negotiations.

The scale of the human tragedy of the First World War was unprecedented. Of 65 million men mobilised, over half were killed, wounded or captured. Over 2 million British servicemen were wounded, their suffering is captured in Lobley's paintings of soldiers with severe facial wounds recovering at Sidcup Hospital [ART 3756], and in the film Repairing War's Ravages [IWM 1098]. The plight of Belgian refugees of the First World War is captured in the photographic collections of the museum, and the work of the relief agencies is also well documented.

More than any other conflict, the Second World War brought civilians into the front line, as indiscriminate bombing destroyed millions of homes in Europe's cities. On the Eastern front, the war was a brutal clash of ideologies, with millions of civilians systematically murdered, or used as slave labour, whilst prisoners of war were allowed to die of starvation and disease.

After the war, the United Nations Rehabilitation and Relief Agency (UNRRA) oversaw the repatriation of 6,173,000 displaced persons from Germany, 870,613 from Austria, and 91,986 from Italy by June 1947. The monumental work of UNRRA is well recorded in the Museum's collections in documents, photographs and printed accounts. The devastation of Europe's cities is depicted in the film Naples is a Battlefield [CVN 218], whilst the practical problems of administering post-war Germany are documented in the film A Defeated People [CVN 252].

The legacy of the First and Second World Wars was the decline of the Great European Powers, and the emergence of the United States and Soviet Union as superpowers. A section of the Berlin Wall, symbol of the period known as the 'Cold War' is on display outside the entrance of the Museum's Lambeth Road site.

Whereas the Twentieth Century has been fundamentally shaped by war, the values of peace have found eloquent expression from political and spiritual leaders, such as Mahatma Gandhi and the Dalai Lama, and have found a popular voice in mass protest movements in Europe and the United States.

Opposition to war, traditionally advocated by religious groups such as the Quakers, gained a stronger political dimension in Britain, with the introduction of conscription in 1916. Although the right to conscientious objection was embodied in law, men were imprisoned for refusing military service, and often vilified by their community. The personal experiences of conscientious objectors of both World Wars are recounted in the documents, books, and oral history recordings.

Following the Second World War, the peace movement in Britain - particularly groups such as the Quakers and the Peace Pledge Union - focused its attention on the prospect of nuclear war. The Campaign for Nuclear Disarmament has followed a campaign of non-violent direct action in advocating unilateral nuclear disarmament by the UK since 1958. During the mid 1960s and 1970s, the focus of the peace movement shifted to opposition to American involvement in Vietnam. The deployment of Cruise missiles in Europe in 1982 caused a wave of protest across the continent. A women-only peace camp remained at RAF Greenham Common, throughout their deployment until 1991. The experiences of these women are documented in oral history recordings. From posters, leaflets and pamphlets produced by groups protesting against Polaris or the Vietnam War, to wire cutters used in CND protests, and film and sound archive materials on protests against conflicts in the Falklands and the Gulf, the Museum's holdings on the Peace Movement are rich and varied.

International efforts to achieve peace and avert conflict have been an important aspect of twentieth century diplomacy. After the failure of the League of Nations, the United Nations was founded at the end of the Second World War. The United Nations has been heavily engaged in mediating in international disputes, brokering peace settlements through diplomacy, and monitoring cease-fires between combatants. Since the first UN brokered peace mission to monitor a cease-fire during the first Arab/Israeli War in June 1948, 55 peacekeeping missions have been mounted, of which 13 are still in operation. Examples of the range of the Museum's holdings on peacekeeping missions include items of UN uniforms, such as badges of the peacekeeping forces in Bosnia and Somalia, a rocket launcher from Bosnia, film of UN operations including Cyprus, Somalia and Rwanda, and recorded interviews with people who had served in Congo, Cyprus, and Bosnia.

The reporting of the brutal fighting in Bosnia from 1992 to 1995 brought home to the world the awful truth of the war crimes perpetrated against the Bosnian Muslim population, most notably at Srebrenica. Such terrible war crimes, characteristic as they are of warfare in the Twentieth Century, are well documented in the Museum's collections.

The transcripts of the proceedings of and selected court papers relating to the International Military Tribunals held at Nuremburg are held as part of the Museum's collections. In addition, the trials are covered in the film World Pictorial News No 241 [WPN 241], in a number of images in the Photograph Archive, and in recorded interviews with persons who worked at the Tribunals, and witnesses to the atrocities of the SS. The Far East International Military Tribunal held in Tokyo is covered in detail too. There are transcripts of the proceedings, and the film Welt im Film No 192 [WIM 192]. A recorded interview with a witness to the Japanese attack on the Alexandra Hospital in Singapore also exists. Important items of film cover the Katyn Massacre Im Wald Von Katyn [GWY 733], and Japanese Atrocities in Nanking [MGH 2843].