Arbuthnot was commissioned in the
Royal Artillery on 17 February 1886. He served in the
Chitral Expedition of 1895 in the
North-West Frontier Province, where he was awarded a medal with clasp, and the following year was promoted to
captain on 30 September 1896. He later served in the
Second Boer War in South Africa from 1899 to 1902, being
mentioned in despatches. He was promoted to
major on 28 October 1901, and in January the following year was appointed an assistant staff officer for colonial forces in South Africa. After the end of the war in June 1902, Arbuthnot stayed in South Africa for several months, returning home on the SS
Scot in November. By the time the
First World War broke out, Arbuthnot had risen to
lieutenant colonel and was Officer Commanding of the
44th (Howitzer) Brigade Royal Field Artillery, based at
Brighton. On mobilisation, the brigade formed part of the artillery of the
2nd Division in the original
British Expeditionary Force. Arbuthnot commanded the Brigade until May 1915, when he became Commander Royal Artillery of the newly formed
28th Division. Although the division spent only ten months on the
Western Front before re-deploying to
Salonika, it took part in several engagements at
Second Battle of Ypres and in the
Battle of Loos. Arbuthnot spent much of the rest of the war away from the Western Front. He was Brigadier General, Royal Artillery of the
XII Corps at Salonika from January to July 1916, Commander Royal Artillery of the
23rd Division in France and Italy from January 1917 to July 1918, and Brigadier General, Royal Artillery of the
XXIII Corps, Home Forces, from July 1918 to the
Armistice. During the war, he was mentioned in despatches eight times, awarded the
Distinguished Service Order, appointed a
Companion of the Order of St Michael and St George in 1915, and made
brevet colonel in 1916. He was also a member of the Italian
Order of Saints Maurice and Lazarus, and was made an honorary brigadier general in 1920. In the first years of the
Second World War, Arbuthnot served with the
Civil Defence. ==Family==