The 9th Heavy Battery, Royal Garrison Artillery, was one of the first British Army units recruited for 'Kitchener's Army' in World War I. It served on the Western Front from 1915 to 1918, supporting different formations of the British Expeditionary Force (BEF). It was overrun and lost its guns at the Chemin des Dames in May 1918 but, re-equipped, it participated in the final Allied Hundred Days Offensive.