The 20th (Light) Division was an infantry division of the British Army, part of Kitchener's Army, raised in the First World War. The division was formed in September 1914 as part of the K2 Army Group. The division landed in France July 1915 and spent the duration of the First World War in action on the Western Front. The division was disbanded after the end of the war in early 1919.

The New Army, often referred to as Kitchener's Army or, disparagingly, as Kitchener's Mob, was an (initially) all-volunteer portion of the British Army formed in the United Kingdom from 1914 onwards following the outbreak of hostilities in the First World War in late July 1914. It originated on the recommendation of Herbert Kitchener, then the Secretary of State for War to obtain 500,000 volunteers for the Army. Kitchener's original intention was that these men would be formed into units that would be ready to be put into action in mid-1916, but circumstances dictated the use of these troops before then. The first use in a major action of Kitchener's Army units came at the Battle of Loos.