He served two years in the Royal Wiltshire Yeomanry,
joined the Scots Guards as Ensign and Lieutenant and then Captain
in 1867; and Lieutenant-Colonel in 1876; and regimental Major in 1882.
He also served as adjutant of the 1st battalion from 1864 until 1871,
held several staff positions such as brigade major, Home District
from 1871-1878, military attaché in Berlin (1878-1881), assistant
adjutant and quartermaster general, Home District (1881-1884), and
deputy adjutant-general, in South Africa (1888-1890). He saw active
duty at Amoaful in the Ashanti campaign of 1873 - 1874 on the staff
of Sir Garnet Wolseley and was the commandant of headquarters in Egypt
for three months in 1882, being present at the Battle of Tel al-Kebir.
He became brevet-colonel in 1881 and served in the expedition of Sir
Charles Warren to Bechuanaland in 1884-1885, where he commanded Methven's
Horse, a corps of mounted rifles. He was promoted to substantive colonial
in 1888, major-general in May of 1888, and commanded the Home District
from 1892-1897. He served in 1897 as press censor at headquarters
on the Tirah expedition and was promoted to lieutenant-general in
1898. He was then given the command of the 1st Division on the outbreak
of the South African War.
He reached South Africa in 1899 and expelled the Boers
from Belmont and Graspan. He was slightly wounded at Modder River.
He suffered both defeats and successes during the war. His greatest
defeat was at the Battle of Magersfontein, for which he was best remembered.
He was also captured, by General Koos de la Rey's commando, badly
beaten and wounded at Tweebosch on 7th March 1902.
Despite these visible setbacks, Methuen continued
to be well regarded, and was given more responsibilities. He was appointed
colonel of the Scots Guards in 1904, then general, and in June was
given the command of the IV Army Corps. He became instrumental in
helping raise the standards of training of the British Expeditionary
Force in 1914. In 1908 he was appointed general officer commanding-in-chief
in South Africa, which he hed until 1912. He was a popular with his
troops as well as his former opponents, and helped improve relations
between the British and the Boers, to give the Union of South Africa
a good start. He was governor and commander-in-chief of Natal in 1910
and was promoted to field-marshal in 1911. At age 70 in 1915, he was
appointed governor and commander-in-chief of Malta until he retired
in 1919. Returning to England he was appointed constable of the Tower
late in 1919.
Lord Methuen was married twice, first to Evelyn,
the eldest daughter of Sir Frederick Hutchingson Hervey-Bathurst,
third baronet of Clarandon Park, Wiltshire. They were married in 1878
until her death in 1879. He then married in 1884, his cousin Mary
Ethel, the second daughter of William Ayshford Sanford, of Nynehead
Court. They had three sons and four daughters. Lord Methuen died at
Corsham Court on October 30, 1932 and was succeeded by his son Paul
Ayshford Methuen, 4th Baron Methuen.