How Many US Citizens Fought in British and Allied Wars?

Britain and the United States have long been allies in military conflicts, forging the so-called special relationship during the 20th and 21st centuries. It wasn’t always this way, however, with Britain and America battling fiercely during the American War of Independence.

The War of 1812 was the last time the US and the UK fought, as part of Britain’s conflict with Napoleon. Here we describe some of the wars that Britain and the USA have fought together and the number of US citizens involved in each. You can find information about the servicemen involved in these battles by searching now with Forces War Records.

The Opium Wars

The Opium Wars were fought in the mid-1800s between the Qing Dynasty and the British Empire over the illegal smuggling of opium by the East India Trading Company into China. Although no official alliance was made, the United States sent envoys to Hong Kong to assist in the war, which crescendoed in the Battle of the Barrier Forts in Guangdong. The assault was launched against four forts and involved the US Navy as well as a landing of 150 marines in Canton – modern-day Guangzhou.

Korean War

The Korean War is largely seen as a product of the Cold War between the US and the Soviet Union and was sparked when North Korea invaded South Korea. South Korea was supported by The United Nations, including both the USA and the UK. This war saw more than 140 thousand US citizens either killed or wounded and many thousands more fighting as part of the United Nations support of South Korea.

World War One and World War Two

World War One and World War Two are both undoubtedly the two bloodiest wars in human history, with many many millions perishing as a result. In both wars, the Americans started off as a neutral power but supplied great Britain and its allies with food, oil and war materials and then joined later on.

In World War One, the US supplied more than four million servicemen with over 100,000 deaths. In the Second World War, an astonishing 16 million military personnel served – over 10% of the American population at the time.

Other Wars

The USA and Britain have fought and died alongside each other in a number of other wars, including The Gulf War and The Global War on Terror; a war that still rages on and is taking place across the globe.

Forces War Records: Discovering Your Ancestry

Here at Forces War Records, we are a leading British military community with over a million members and we can help you discover whether any of your ancestors fought in these wars. Our researchers study Britain’s military history and have published a number of books and articles on the subject. We can help you in your quest to discover your family’s military history with our archive of exclusive military records.


To find out more, please feel free to contact us today and search now to find out more about your own military ancestry. You can email us at