United Kingdom

The United Kingdom of Great Britain and Northern Ireland (commonly known as the United Kingdom, the UK, or Britain) is a sovereign state located off the northwestern coast of continental Europe. It is an island country, spanning an archipelago including Great Britain, the northeastern part of Ireland, and many small islands. Northern Ireland is the only part of the UK with a land border, sharing it with the Republic of Ireland. Apart from this land border, the UK is surrounded by the Atlantic Ocean, the North Sea, the English Channel and the Irish Sea. The largest island, Great Britain, is linked to France by the Channel Tunnel.

The United Kingdom has appeared in all Call of Duty games so far, with the exception of the home console (excluding the PS2 and PC releases of World at War).

In Call of Duty
British World War II campaigns provide the setting for Call of Duty 1, 2, and 3.

Call of Duty: World at War
Although initially it was thought there was no British campaign in Call of Duty: World at War, the discovery of code within the game showing British weapons hinted one had been planned but dropped last minute. Notably the icon for the weapon selection menu and HUD icon portraying the Bren gun are still in the game's files. Evidence of the Sten gun and Lee-Enfield rifle has also been found. There is, however, a British campaign in Call of Duty: World at War: Final Fronts and Call of Duty: World at War DS.

Counter-terrorism in Ukraine (1996)
The British Special Air Service attempted an assassination on Russian Ultranationalist terrorist Imran Zakhaev in the Chernobyl Zone of Alienation in a flashback sequence in Call of Duty 4.

Second Russian Civil War (2011)
The British Special Air Service is involved with United States Marines and Russian Loyalists in covert operations against the Russian Ultranationalists and Middle Eastern OpFor in the Bering Strait, Russia, and Azerbaijan in the majority of the Call of Duty 4: Modern Warfare plot.

Russian-American War (2016)
Numerous British operatives (eg. Simon "Ghost" Riley) are seen as a part of Task Force 141, an elite paramilitary group dedicated to continuing their fight against the Russian Ultranationalists. It is also known that Makarov bombed Piccadilly Circus in London.