In United Kingdom, the British military has a long history, a global presence, and a wide range of missions and responsibilities; these responsibilities include protecting the UK, its territories, national interests, and values, preventing conflict, providing humanitarian assistance, participating in international peacekeeping, building relationships, and fulfilling the UK’s alliance and treaty commitments; in addition to its role in the UN, the UK is a leading member of NATO and has made considerable military contributions to NATO missions in such places as Afghanistan, the Baltics, and Iraq, as well the Baltic and Mediterranean seas and the waters of the North Atlantic

the UK is a member of the Five Power Defense Arrangements (FPDA), a series of mutual assistance agreements reached in 1971 embracing Australia, Malaysia, New Zealand, Singapore, and the UK; in 2014, the UK led the formation of the Joint Expeditionary Force (JEF), a pool of high-readiness military forces from the Baltic and Scandinavian countries intended to respond to a wide range of contingencies both in peacetime and in times of crisis or conflict; the UK military also has strong bilateral ties with a variety of foreign militaries, particularly the US, with which it has a mutual defense treaty; British and US military forces have routinely operated side-by-side across a wide range of operations; other close military relationships include Australia, France, and the Netherlands; in 2010, for example, France and the UK signed a declaration on defense and security cooperation that included greater military interoperability and a Combined Joint Expeditionary Force (CJEF), a deployable, combined Anglo-French military force for use in a wide range of crisis scenarios, up to and including high intensity combat operations

the British Armed Forces were formed in 1707 as the armed forces of the Kingdom of Great Britain when England and Scotland merged under the terms of the Treaty of Union; while the origins of the armed forces of England and Scotland stretch back to the Middle Ages, the first standing armies for England and Scotland were organized in the 1600s while the navies were formed in the 1500s; the Royal Marines were established in 1755; the Royal Air Force was created in April 1918 by the merger of the British Army's Royal Flying Corps and the Admiralty's Royal Naval Air Service (2024)