Major General William Holmes was a senior Australian Army officer during the First World War. He was mortally wounded by a German artillery shell while surveying the ground won at the Battle of Messines.

The Battle of Messines was an attack by the British Second Army, on the Western Front, near the village of Messines in West Flanders, Belgium, during the First World War. The Nivelle Offensive in April and May had failed to achieve its more grandiose aims, had led to the demoralisation of French troops and confounded the Anglo-French strategy for 1917. The attack forced the Germans to move reserves to Flanders from the Arras and Aisne fronts, relieving pressure on the French.