Lillers was used for billets and headquarter offices from the autumn of 1914 to April 1918. At that time it was a hospital centre with the 6th, 9th, 18th, 32nd, 49th and 58th Casualty Clearing Stations in the town at one time or another. In April 1918, the Germans advanced as far as Robecq; Lillers came under shell-fire, and the units holding this front continued to bury beyond the cemetery boundary, in the extension.