Fitzgibbon, (Robert Louis) Constantine (Lee-Dillon) (1919–83), writer, was born 8 June 1919 in Lenox, Massachusetts, USA, fourth child and only son of Robert Francis Lee-Dillon Fitzgibbon (1884–1954) and his wife Georgette, daughter of George Winthrop Folsom of Lenox, Massachusetts. Robert Francis Fitzgibbon, a direct descendant of John FitzGibbon (qv), 1st earl of Clare, was an unstable character who was a successful cotton broker in New York (1908–14) and was in the Royal Navy during the first world war before being discharged as a drug addict. He afterwards joined the French Foreign Legion. He was divorced by his wife in 1923, remarried, and had little contact with his children. Constantine was brought up in Lenox and New York until 1927, when his mother married her cousin Bertram Winthrop, and the family moved to Paris (she divorced again in 1931).
Constantine attended Wellington College, England, on a scholarship from 1933 until he was asked to leave in 1935, after a scandal in which he was accused of sexually corrupting the other boys. He was briefly in art school in Munich before proceeding to Paris to study in the Sorbonne and winning (December 1936) an open modern-language scholarship to Oxford. He attended Exeter College, edited his own magazine, Yellowjacket, and had poetry and prose published, but he left Oxford without a degree in 1939. He married that year (27 October 1939) Margaret Aye Young, a beautiful half-Irish, half-Burmese student of Somerville College, but they rapidly separated. The following year he joined the Irish Guards, but later transferred to the Oxford and Buckinghamshire Light Infantry and in 1942 to the American army, where he was appointed major and was employed in intelligence work in London and Washington. After the war he edited a book on the German general staff, and his research was used at the Nuremberg war crimes tribunal.
Deciding to become a writer, he left the army in 1946 and moved to Bermuda with his second wife, Theodora Rosling (Theodora Fitzgibbon (qv)), the future cookery writer, whom he had married 21 March 1944. He worked as a schoolteacher in Saltus grammar school, Bermuda, and wrote and subsequently had published two novels, The Arabian bird (1949) and The iron hoop (1950). Offered the chance to write the biography of the writer Norman Douglas, he moved in 1948 with his wife to Capri, where Douglas was living. There he remained two years, though the biography was never completed; the most he achieved was a book of photographs, Norman Douglas: a pictorial record (1953). This was an extremely rare instance of unfinished work; Fitzgibbon was hugely prolific and published in his lifetime over thirty works of fiction and non-fiction, and forty translations from German, French, and Italian works.
His years of industry began on his return to England from Capri in 1950, when he bought with his wife a house in Sacomb's Ash, Hertfordshire. In his nine years there he translated thirty books and wrote nine more, at a time when he was developing a serious drink problem. He recounts in Drink (1979) how he would work all morning, hit the pub for lunch, return to work, and then repair to the pub at evening. This took its toll on his marriage, as did both his and his wife's infidelities, and in 1959 they divorced. The following year (27 August 1960) he married Marion McFadyean (née Gutmann) and bought Waterson Manor, near Dorchester, after his seventh novel, When the kissing had to stop (1960), became a bestseller. A thriller in the style of Orwell's 1984, it describes a Labour government in Britain becoming a pawn of the Soviet Union, and marked Fitzgibbon's growing disenchantment with the Soviet regime after a youthful interest in Marxism. The televising of the novel in 1962 landed Fitzgibbon in controversy and an accusation in liberal circles of being a fascist. He responded by publishing a collection of his former political essays entitled Random thoughts of a fascist hyena (1963), in which he equated Soviet Russia with Nazi Germany. Reviewing this book in the New Statesman (13 September 1963), Conor Cruise O'Brien described the author as ‘an intellectual propagandist with a gift for blurring distinctions’. Fitzgibbon's friends found him emotional – even hysterical – over politics, and so not always to be trusted, but they appreciated his warmth and geniality.
None of Fitzgibbon's subsequent novels were bestsellers but in 1965 he achieved a non-fiction success with the publication of the authorised biography of his close friend Dylan Thomas. In his youth Fitzgibbon was part of Thomas's Soho set, and his biography successfully recreates the bohemian milieu. However, his drinking was still not under control and that year his third wife divorced him, taking custody of their son. The following year he met at a health resort Marjorie Sutton (née Steele), a Californian actress who, like him, was an alcoholic and twice divorced. They were married in 1967 and that year settled permanently in Dublin, where they had a daughter.
His enthusiasm for his father's country led to Fitzgibbon's applying for and receiving Irish citizenship in 1970 and writing a plethora of books on Irish history including Out of the lion's paw: Ireland wins her freedom (1969), a novel on Michael Collins (qv), High heroic (1969), and Red hand: the Ulster colony (1971). These were popular histories relying exclusively on secondary sources and evincing a strong nationalist bias; they do not show the capacity for diligent research proved by his Dylan Thomas biography. During the 1970s Fitzgibbon wrote frequently about Northern Ireland to the Times and (confidentially) to the British ambassador in Dublin, denouncing the methods of the IRA but also deploring the attitude of the British government.
He finally swore off drink after a stint in the St John of God's hospital in Dublin in 1978. The next year he published Drink (1979), both an autobiography and a study of alcoholism, which brought out his strengths as a writer: his searing honesty and his ability to establish intimacy with the reader. He died 23 March 1983 in hospital in Dublin.