Somerville, Henry Boyle Townshend (1863–1936), naval officer, hydrographer, and author, was born 7 September 1863 on his family's historic estate at Drishane, Castletownshend, near Castle Haven, Co. Cork, third son of Lt.-col. Thomas Henry Somerville (later high sheriff of Cork) and his wife, Adelaide Eliza, tenth daughter of Adm. Sir Josiah Coghill and his wife, Anna Maria, daughter of Charles Kendal Bushe (qv), lord chief justice of Ireland. He had five brothers – Thomas Cameron Fitzgerald, Joscelyn Josiah Coghill (who died in infancy), Aylmer Coghill, John Arthur Coghill, and Hugh Gualtier Coghill (also an admiral) – and two sisters, Edith Anna Œnone Somerville (qv), renowned author of the Irish RM stories, and Elizabeth Hildegarde Augusta. His family (whose genealogy he studied in great detail) was descended from a late seventeenth-century Scottish episcopalian clergyman of Galloway, who moved to Ireland in 1692 to avoid religious persecution at home and whose descendants prospered in Co. Cork. Somerville (known as Boyle) was educated at the Royal Naval Academy, Gosport, and HMS Britannia. Always excited by adventure, he served (1880) in the Shannon (to which he subsequently returned), in the Chilean–Peruvian war (1879–83), and with the Agincourt in the first Egyptian war (1882). He later served in the Audacious and the Heroine in China (1884–8) and in the Dart in New Zealand (1889). As a hydrographer he worked for the admiralty on its hydrographic surveys of Australia and the western Pacific (1889–96), extending to the eastern Pacific (1897–1900) aboard Egeria. He surveyed the Persian Gulf (1902) with HMS Sphinx, and Ceylon and the Indian ocean (1904–7, including the Percy Sladen research expedition) aboard Sealark, returning to survey British coastal waters (1908–14) in Research. During these expeditions, and throughout his naval career, he returned to Castletownshend as often as opportunity would allow.
His service in the first world war (1914–18) was equally diverse; he commanded the Victorian, Argonaut, Amphitrite, and King Alfred in the north Atlantic until 1916 with the 10th Cruiser Squadron. He commanded the Devonshire in 1917 as senior naval officer at Halifax, Nova Scotia, and on convoy service between Britain and America. He then served at the admiralty in London until his retirement in the rank of vice-admiral in August 1919. He was also created CMG and an officier of the Légion d'honneur in that year. In retirement he was reemployed by the admiralty's hydrographic department and was chairman of its tidal committee in 1923. He wrote admiralty reference works, including Ocean passages for the world (published 1923).
As an author Somerville had an enquiring mind (which accommodated both his anglo-catholic conservatism and his anti-union political views, which supported home rule for Ireland) and an accessible writing style, which resulted in other valuable books and essays on subjects ranging from maritime to archaeological matters. As well as dictionaries of Pacific languages he had encountered in the New Hebrides, New Georgia, and the Solomon Islands, he wrote vivid historical works including The chartmakers (1928), Commodore Anson's world voyage (1934), and Will Mariner (1936), the last of which was practically completed at his death and was subsequently edited for publication by his sister Edith. His articles appeared in Blackwood's Magazine, Atlantic Monthly, Antiquity, and the Journals of both the RSAI and the Cork Historical and Archaeological Society, of which latter organisation he was vice-president at the time of his assassination.
He married (1896) Helen Mabel (‘Mab’), youngest daughter of Sir George Wigram Allen, KCMG, and his wife, Marian (née Boyce), both of Sydney, whom he met while surveying the Pacific region. They had three sons – Thomas Raymond, Brian Aylmer, and Michael Fitzgerald – and one daughter, Diana Marian. They occupied naval quarters abroad until retiring to Point House, Castletownshend, when Somerville finally left the maritime service in 1924.
His Cork idyll, where he had begun to study the Irish language and defined his recreation as ‘archaeological exploring’, came to a violent end at 9.30 p.m., 24 March 1936; the IRA arrived at Point House and shot him dead for providing references, as a matter of courtesy, to local boys seeking to join the Royal Navy. Somerville's assailants left a note accusing him of being a British recruiting agent. He was killed one month after another fatal IRA attack in Longford. His sister Edith later recalled visits by more than 300 of ‘the admiral's boys’ asking his advice, and whom he could never refuse, believing the navy life to be worthwhile and character-forming. His assassination shocked the country and the Fianna Fáil government of Éamon de Valera (qv) in particular, which, after the further assassination in April of ex-IRA member John Egan in Dungarvan, Co. Waterford, proscribed the IRA (18 June 1936). Somerville's widow outlived him until 28 June 1962. His own death long remained a byword for the futile, sporadic violence that lingered in the early years of Irish independence. Curiously, Somerville was posthumously credited in 1940 as co-author, with his sister Edith, of Records of the Somerville family, in which she claimed that through the intervention of a medium he returned in ghostly form to assist her in the completion of the book. As an author, living or otherwise, Somerville's greatly neglected works deserve revived interest, proving a legacy greater than the tragic incident for which he is remembered.