He served as an army officer with the Royal Artillery in World War II, being captured at the Japanese taking of Singapore in 1942, but escaping, before seeing further active service in Burma. In May 1943, by then a temporary major, he was appointed an Officer of the Order of the British Empire, for distinguished service in the South-West Pacific theatre. He reached the rank of Lieutenant-Colonel in 1945, and was promoted to the substantive rank of major on 1 July 1946. On 1 April 1954, he was promoted to lieutenant colonel, and retired from the regular army on 31 December 1957. He was appointed an Honorary Colonel in 1967. He inherited the Bodrhyddan estate in Rhuddlan, on the death of his unmarried and childless paternal uncle CaptainRafe Grenville Rowley-ConwyRNCMG in April 1951 and succeeded to the Barony as the ninth holder of the title on the death of his childless second cousin once removed Arthur Sholto Langford Rowley, 8th Baron Langford CMG in August 1953. He was Constable of Rhuddlan Castle and Lord of the Manor of Rhuddlan. He turned 100 in March 2012. He died on 12 November 2017 at the age of 105.
Marriage and children
He married, firstly, Ruth St John Murphy, on 24 January 1939. She was the daughter of Albert St John Murphy and Rose Davis, of The Island House, Little Island, County Cork, Ireland. They divorced in 1956. They had no children. He married, secondly, Grete von Freiesleben, on 7 February 1957. She was the daughter of Colonel Erik Theodor Christian von Freiesleben, of Hjortekaer, Kongens Lyngby, Copenhagen, Ch Kings's Adj's Staff to His Majesty The King of Denmark. They had three children and seven grandchildren:
Hon. John Seymour Rowley-Conwy ; he married Emma Brown in 1983. They have three children:
*Katherine Grete Clare Rowley-Conwy
*William Geoffrey Peter Rowley-Conwy
*Huw Grenville Rowley-Conwy
Owain Grenville Rowley-Conwy, 10th Baron Langford ; he married Joanna Featherstone on 3 May 1986. They have two children:
*Hon. Thomas Alexander Rowley-Conwy
*Hon. Magdalene Guinevere Rowley-Conwy
He married, thirdly, Susan Winifred Denham, daughter of Cyril Henry Charles Denham, of Wrexham, Denbighshire, Wales, on 3 February 1975. Lady Langford is a patron of St Kentigern Hospice, St Asaph. They have two children:
Hon. Christopher Geoffrey Hugh Rowley-Conwy ; he married Robina Khan on 25 August 2007.
Hon. Charlotte Susan Gabrielle Rowley-Conwy.
He was succeeded by his third son from his second marriage, Hon. Owain Grenville Rowley-Conwy.