The British Army historically included many units from what are now separate Commonwealth realms. When the English Empire was established in North America, Bermuda, and the West Indies in the early 17th century there was no standing English Army, only the Militia, Yeomanry, and Royal bodyguards, of which the Militia, as the primary home-defence force, was immediately extended to the colonies. Colonial militias defended colonies single-handedly at first against indigenous peoples and European competitors. Once the standing English Army, later the British Army, came into existence and began to garrison the colonies, the colonial militias fought side by side with it in a number of wars, including the Seven Years' War. Some of the colonial militias rebelled during the American War of Independence. The militia fought alongside the regular British Army (and native allies) in defending British North America from their former countrymen during the War of 1812.
Locally raised units in strategically located Imperial fortress colonies (including: Nova Scotia before the Canadian Confederation; Bermuda - which was treated as part of The Maritimes under the Commander-in-Chief at Nova Scotia until Canadian Confederation; Gibraltar; and Malta) and the Channel Islands were generally maintained from army funds and more fully integrated into the British Army as evident from their appearances in British Army lists, unlike units such as the King's African Rifles.
The larger colonies (Australia, New Zealand, Canada, South Africa, etc.) mostly achieved Commonwealth Dominion status before or after the First World War and were granted full legislative independence in 1931. While remaining within the British Empire, this placed their governments on a par with the British government, and hence their military units comprised separate armies (e.g. the Australian Army), although Canada retained the term "militia" for its military forces until the Second World War. From the 1940s, these dominions and many colonies chose full independence, usually becoming Commonwealth realms (as member states of the Commonwealth are known today).
Units raised in self-governing and Crown colonies (those without local elected Legislatures, as was the case with British Hong Kong) that are part of the British realm remain under British Government control. As the territorial governments are delegated responsibility only for internal government, the UK Government, as the government of the Sovereign state, retains responsibility for national security and the defence of the fourteen remaining British Overseas Territories, of which six have locally raised regiments:
· Royal Bermuda Regiment
· Royal Gibraltar Regiment
· Falkland Islands Defence Force
· Royal Montserrat Defence Force
· Cayman Islands Regiment
· Turks and Caicos Regiment