On the outbreak of the
First World War in August 1914, Miller was transferred to the
Sherwood Foresters (Nottinghamshire and Derbyshire Regiment). He was appointed
adjutant and in January 1915 was made a temporary captain. Serving with the 1st Battalion, he arrived in France on 1 March 1915 and soon after was awarded the
Military Cross for his bravery and leadership in action. He subsequently served as a
brigade major from November 1915 to February 1917 and as
General Staff Officer (GSO) Grade 2 from February 1917 to October 1918. For his services he was given the
brevet of
major in January 1918, was three times
mentioned in despatches, awarded a
Bar to his Military Cross and awarded the French
Croix de Guerre. Miller subsequently served as an instructor at the
Staff School, Cambridge and as GSO 2 in France and with the
British Army on the Rhine until June 1919. After attending the
Staff College, Camberley, from 1921 to 1922, Miller then held appointments as brigade major in England, with the British Army on the Rhine, and in India. He was promoted brevet
lieutenant-colonel in July 1929 and lieutenant-colonel in January 1936. He served as commanding officer of the 1st Battalion, Sherwood Foresters from 1936 to 1937, was promoted to colonel in October 1937, and appointed GSO 1 Northern Command until 31 September 1939. Promoted to acting brigadier on 1 October 1939 and temporary brigadier in March 1940, Millar was in command of the
164th (North Lancashire) Brigade, Home Forces until April 1941. Miller also served as
aide-de-camp to
King George VI from February 1940 to November 1941. He was appointed Deputy Adjutant & Quartermaster General of Scottish Command from April to May 1941. Promoted to acting major-general in April 1941 and confirmed in that rank in November 1941, he was in charge of administration of Scottish Command until his retirement in 1945. For his wartime services he was appointed a
Companion of the Order of the Bath in 1942. Miller died on 16 May 1947. ==References==