List of wars involving the United Kingdom in the 21st century

This is a list of military conflicts, involving the United Kingdom in the 21st century.

For the criteria of what may be permitted on this list, see List of wars involving the United Kingdom.

Key

List

Conflict Allies Opponent(s) Outcome Sierra Leone Civil War(1991–2002)

Revolutionary United Front Armed Forces Revolutionary Council West Side BoysBritish allied victory Rebels defeated. War in Afghanistan(2001–2021)

International Security Assistance Force Taliban Inconclusive or other outcome The Taliban militia, overthrown in 2001. British withdrawal in 2014. Taliban regained power on 15 August 2021, after 20 years of NATO deployment. Iraq War(2003–2011)

Islamic State of Iraq Various Iraqi insurgentsBritish allied victory Overthrow of Ba'ath Party government. Occupation of southern Iraq. Iraqi insurgency, emergence of al-Qaeda in Iraq, and civil war in Iraq (2006–07). Rise and defeat of the Islamic State, the successor of al-Qaeda in Iraq.Somalian Civil War (1991–present) Al-Qaeda Al-Shabaab and allies

Somaliland Armed Forces and alliesOngoing Somalian military takes at least a third of Al-Shabaab territory in 2022. Ongoing constitutional crisis in Somalia since 2023. Jubaland crisis since 2024.Operation Ocean Shield (2009–2016)

Non-NATO forces:

ColombiaSomalian piratesBritish allied victory The anti-piracy operation follows the earlier NATO Operation Allied Protector. NATO's contribution to Operation Enduring Freedom – Horn of Africa. Number of pirate attacks dramatically decreased. Piracy drops 90 % in 2013. Action of 11 November 2008. First Libyan Civil War(2011) Many NATO members acting under UN mandate, including:

and Anti-Gaddafi forces several Arab League states

Libyan Arab Jamahiriya Pro-Gaddafi forcesBritish allied victory Fall of the Libyan Arab Jamahiriya. Muammar Gaddafi killed. National Transitional Council takes control. Operation Shader(2014–present) Boko Haram

al-Nusra Front Khorasan

Ahrar ash-ShamOngoing The UK's Operation Shader is ongoing as part of the war against the Islamic State. Over 3 000 IS fighters killed in 1 700 British airstrikes. Ongoing operations by British special forces in Syria. British military provides materiel and training to the Iraqi military. IS loses all territory in Iraq in December 2017 and Syria in March 2019. Operation Prosperity Guardian(2023–2025) Part of the Red Sea crisis, Middle Eastern crisis, and the Yemeni Civil War United States Supreme Political Council Inconclusive or other outcome US-led multinational coalition formed in December 2023 to respond to attacks on shipping in the Red Sea. Two phases of US–UK airstrikes on Yemen. Operation Southern Spear (2025–present)

Part of the Crisis in VenezuelaOngoing Capture of President Nicholas Maduro. Seizure of "shadow fleet" oil tankers.

See also Declaration of war by the United Kingdom Military history of the United Kingdom British Armed Forces List of British military installations

Notes

References

Further reading Barnett, Correlli. Britain and her army, 1509–1970: a military, political and social survey (1970). Black, Jeremy. A military history of Britain: from 1775 to the present (2008). Bradford, James C. ed. International Encyclopedia of Military History (2 vol. 2006). Brownstone, David and Irene Franck. Timelines of War: A Chronology of Warfare from 100,000 BC to the Present (1996), Global coverage. Cannon, John, ed. The Oxford Companion to British History (2003) Carlton, Charles. This Seat of Mars: War and the British Isles, 1485–1746 (Yale UP; 2011) 332 pages; studies the impact of near unceasing war from the individual to the national levels. Chandler, David G., and Ian Frederick William Beckett, eds. The Oxford history of the British army (Oxford UP, 2003). Cole, D. H and E. C Priestley. An outline of British military history, 1660–1936 (1936). online Dupuy, R. Ernest and Trevor N. Dupuy. The Harper Encyclopedia of Military History: From 3500 B.C. to the Present (1993). Fortescue, John William. History of the British Army from the Norman Conquest to the First World War (1899–1930), in 13 volumes with six separate map volumes. Available online for downloading; online volumes; The standard highly detailed full coverage of operations. Haswell, Jock, and John Lewis-Stempel. A Brief History of the British Army (2017). Higham, John, ed. A Guide to the Sources of British Military History (1971) 654 pages excerpt; Highly detailed bibliography and discussion up to 1970; includes local and naval forces. James, Lawrence. Warrior Race: A History of the British at War (Hachette UK, 2010). excerpt Johnson, Douglas, et al. Britain and France: Ten Centuries (1980) Mulligan, William, and Brendan Simms, eds. The Primacy of Foreign Policy in British History, 1660–2000 (Palgrave Macmillan; 2011) 345 pages timeline pp xix to xxxi Otte, T.G. The Makers of British Foreign Policy: From Pitt to Thatcher (2002) Ranft, Bryan. The Oxford Illustrated History of the Royal Navy (Oxford UP, 2002). Rodger, N. A.M. The safeguard of the sea: A naval history of Britain, 660–1649 (Vol. 1. 1998). excerpt Rodger, N.A.M.The Command of the Ocean: A Naval History of Britain, 1649–1815 (vol 2 2006) excerpt Sheppard, Eric William. A short history of the British army (1950). online Ward, A.W. and G.P. Gooch, eds. The Cambridge History of British Foreign Policy, 1783–1919 (3 vol, 1921–23), old detailed classic; vol 1, 1783–1815 ; vol 2, 1815–1866; vol 3. 1866–1919

Historiography Messenger, Charles, ed. Reader's Guide to Military History (2001) pp 55–74 etc.; annotated guide to most important books. Schroeder, Paul W. "Old Wine in Old Bottles: Recent Contributions to British Foreign Policy and European International Politics, 1789–1848." Journal of British Studies 26.01 (1987): 1–25.