Background
Montgomery was the fifth son of the politician Hugh Montgomery and was born at Blessingbourne House, near Fivemiletown, County Tyrone, Ireland.
Montgomery was the fifth son of the politician Hugh Montgomery and was born at Blessingbourne House, near Fivemiletown, County Tyrone, Ireland.
He was educated at Charterhouse School and in 1900 joined the Foreign Office as a clerk.
From 1904 to 1907 he served as Private Secretary to the Under-Secretary of State for Foreign Affairs, and from 1907 to 1910 he was précis writer to the Foreign Secretary, with a brief interlude in 1908 when he served as Assistant Private Secretary to Prime Minister Sir Henry Campbell-Bannerman. In 1918 he was on the staff of the Earl of Reading"s embassy to the United States and in 1919 he was appointed Chief Clerk and Assistant Secretary of the Foreign Office. In 1922 he was promoted to Assistant Under-Secretary of State for Foreign Affairs and in 1930 Deputy Under-Secretary of State.
In 1933 he received his first and only senior overseas posting when he was appointed Envoy Extraordinary and Minister Plenipotentiary at The Hague.
He held this post until his retirement in 1938.