From the mud of the Somme to the raid on Zeebrugge, the Royal Marines fought in almost every element of the Great War on the Western Front. Today they are known worldwide as an elite commando fighting force, but that has only been their role since 1940, a fraction of their period in existence. Until 1923 they existed as two corps – the Royal Marine Light Infantry and the Royal Marine Artillery – and both served with distinction along the western front in the great war. This book examines and explains the engagements in which they were involved, the equipment used and the organization and training undertaken in hitherto unseen detail, drawing on a wide variety of sources to give an accurate picture of their contribution to the war in France and Belgium.