The Kent Fortress Royal Engineers (KFRE) was a volunteer Territorial unit of the British Army that saw service in both World Wars. They are notable for their successful actions in May 1940, when they destroyed substantial oil stocks and installations just ahead of the German advance, and in August 1944 during the assault crossing of the River Seine.

The Army Reserve is the active-duty volunteer reserve force of the British Army. It is separate from the Regular Reserve whose members are ex-Regular personnel who retain a statutory liability for service. The Army Reserve was known as the Territorial Force from 1908 to 1921, the Territorial Army (TA) from 1921 to 1967, the Territorial and Army Volunteer Reserve (TAVR) from 1967 to 1979, and again the Territorial Army (TA) from 1979 to 2014.