 Mobilisation began at the onset of the war , in August 1914 , at which time the 1st King 's was based at Aldershot . Under command of Lieutenant @-@ Colonel W.S. Bannatyne , the 1st King 's boarded the SS Irrawaddy at Southampton . The battalion landed at Le Havre on 13 August with the 6th Brigade , 2nd Division , one of the original components of the British Expeditionary Force ( BEF ) . The BEF first engaged the German Army at Mons , Belgium , after which it went into a retreat that was sustained until 5 September , when the Allies resolved to stand at the Marne , a river east of Paris . Having acted as a rearguard to the 2nd Division , the 1st King 's and its brigade prevented a German force cutting off the 4th ( Guards ) Brigade , forming the rearguard at Villers @-@ <unk> , and 70th Battery , Royal Field Artillery . The brigade extricated the guns , earning it praise from the 2nd Division 's commanding officer , Major @-@ General Monro . 
