Following the outbreak of World War I, Robertson served as Quartermaster General of the British Expeditionary Force (under John French) from 5 August 1914 and then as Chief of Staff of the British Expeditionary Force from 25 January 1915.
Robertson served as Quartermaster General of the British Expeditionary Force (under John French) from 5 August 1914 and then as Chief of Staff of the British Expeditionary Force from 25 January 1915. This was following the outbreak of World War I.