Conflict took place in every year of the 20th Century; the world was free from the violence caused by war for only very short periods of time. It has been estimated that 187 million people died as a result of war from 1900 to the present. The actual number is likely far higher.

The following list highlights just some of the conflicts that have impacted the lives of people from the United Kingdom, the British Empire and the Commonwealth since 1900. The museum records and preserves stories from many of these conflicts amongst its collections. 

Discover more about each conflict by searching IWM's extensive collections.

You will find that each conflict is described with a set of dates, which implies a defined ‘beginning and end’. While this is useful to help with classification, it is important to note that the causes and consequences of individual wars or conflicts extend far beyond these narrow ranges. Frequently, there are wider issues which connect many of them together; exploring and documenting these links through our collections is an ongoing process.


Boer War, 1899–1902

First World War, 1914–1918

Russian Civil War, 1917–1922

Third Afghan War, 1919

Irish War of Independence, 1919–1921

Irish Civil War, 1922–1923

Spanish Civil War, 1936–1939

Arab Revolt in Palestine, 1936-1939

Second World War, 1939–1945

Jewish insurgency in Mandatory Palestine, 1944-1948

Partition of India, 1947

Israeli-Palestinian Conflict, 1948 onwards

Malayan Emergency, 1948–1960

Yangtze Incident, 1949

Korean War, 1950–1953

Kenya Emergency, 1952–1960

Cyprus Emergency, 1955–1959

Vietnam War, 1955–1975

Suez Crisis, 1956

Brunei Revolt, 1962–1963

Indonesian Confrontation, 1963–1966

Aden Emergency, 1963–1967

'The Troubles', 1969–1998

Falklands Conflict, 1982

Gulf War, 1990–1991

Sierra Leone Civil War, 1991–2002

Bosnian War, 1992–1995

Kosovo War, 1998–1999

War in Afghanistan, 2001–2014

Iraq War, 2003–2011

Libya Conflict, 2011–present

Syria Conflict, 2011–present

Yemen Conflict, 2014–present

Global Coalition to Defeat ISIS, 2014–present   

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© IWM (Q 2943)
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IWM (Q 88431)
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IWM books

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