The 4th Battalion, Queen's Royal Regiment (West Surrey) (4th Queen's) was a volunteer unit of the British Army from 1859 to 1961. Beginning from small independent units recruited in the South London suburbs, it was attached to the Queen's Royal Regiment (West Surrey) and served in the Second Boer War, World War I and Third Anglo-Afghan War. Before World War II it was converted into a Royal Artillery searchlight regiment that served in the Battle of Britain and The Blitz. Later it became a light anti-aircraft gun unit serving on blockships in the Mulberry harbour during the Normandy invasion, and then defended the port of Antwerp in the closing stages of the war. Postwar it continued in the air defence role before rejoining the Queen's Regiment as infantry.