Martin à Beckett Boyd was born at Lucerne, Switzerland, in 1893, when his family were on their way home to Australia after one of their periodic trips to England and Europe. His parents, Arthur Merric Boyd (1862-1940) and Emma Minnie Boyd (q.v.) (1858-1936) were both artists of note, while his brothers Merric (1888-1959) and Penleigh (1890-1923) excelled at pottery and painting respectively. On his mother's side Boyd was descended from Gilbert à Beckett, the founder of Punch, while his great grandfather, William à Beckett (q.v.) was first chief justice of Victoria and a poet.
The 1890s financial crash had a severe effect on the family fortune and so Boyd was educated in Melbourne, at Trinity Grammar School and St John's Theological College, but his theological studies were short lived and in 1913 he joined an architectural firm. He frequented Melbourne social events and also spent a lot of time with his cousins the Weigalls, one of whom, Joan, married Daryl Lindsay (qq.v.) and became famous as the author of Picnic at Hanging Rock. During World War I Boyd served in the Royal Flying Corps. His war experiences had a profound effect on him, as can be seen in his autobiographies A Single Flame (1939) and Day of My Delight (1965) and in the anti-authoritarianism and pacifism in novels such as Lucinda Brayford (1946) and When Blackbirds Sing (1962).
In 1919, after his participation in World War One, Boyd returned briefly to Australia, where he published his book of verse, Retrospect (1920). He was soon back in England, where he spent some time in an Anglican Franciscan monastery, before publishing four novels under the pseudonyms of Martin Mills and Walter Beckett, including The Montforts (1928), which was awarded the first gold medal of the Australian Literature Society. Several more novels were published in the 1930s, under his own name, together with a delightful children's book The Painted Princess (1936). In 1946 Lucinda Brayford, considered by some to be his finest work, was published. Shortly after this he returned to Australia and purchased the old family home 'The Grange' at Berwick, outside Melbourne. He commissioned his nephew, the artist Arthur Boyd (q.v.), to paint murals on the walls of 'The Grange' and in the meantime, after discovering his grandmother's diaries, commenced work on the first of the four novels now known as the "Langton Quartet": The Carboard Crown (1952). A Difficult Young Man (1955); Outbreak of Love (1957) and When Blackbirds Sing (1962) followed. These novels trace the history of the Langton family in England and Australia over a period of 80 years. Boyd's use of a narrator produces a fascinating and complex narrative, but the narrowness of social range in these novels of Anglo-Australian aristocracy has often been criticized. Nevertheless, they are admired for their powerful evocation of time and place and their satire of English and Australian life before World War I.
In the early 1950s Boyd returned to England and eventually he sold 'The Grange'. The house was demolished by the new owners and Arthur Boyd's murals were lost. For the last 15 years of his life, Boyd lived in Rome. A few days before his death on 3 June 1972 he was received into the Catholic Church. The question of Boyd's sexuality has often been raised; however, despite his close friendship with a young Italian man during his years in Rome, there is no conclusive evidence that he ever entered into a relationship.