James Britten was born in Chelsea, London. He was educated privately and was, at first, inclined towards a medical career. However, at an early age he had become interested in plants and so in 1869, he accepted a post in the herbarium at Kew. He moved from Kew to the Department of Botany in the British Museum in 1871 and remained there until his retirement in 1909.
He published notes on the plants found near Kew bridge, on the plants of Buckinghamshire and an account of the Crassulaceae (for a Flora of tropical Africa – Flora Capensis). “This was perhaps his most important piece of purely taxonomic work” A B Rendle. He also produced ‘European ferns’, ‘A dictionary of plant names’ and ‘A Biographical Index of British and Irish Botanists’ – the latter in conjunction with George Boulger.
From 1879 to 1924, he acted as Editor of the Journal of Botany (British and Foreign); this became the journal for the records of British plants, descriptions of new species, botanical bibliographies and obituaries. Incidentally, he contributed to the first edition of this journal in 1863, which was his list of rare and exotic plants at Kew Bridge. His editorial contributions were read with considerable interest as he had a ready wit and keen sense of humour, combined with strong views cogently expressed. He had an immense botanical knowledge though he would declare that ‘he could never see anything down a microscope‘.
He was converted to Catholicism in his early twenties and was for many years involved with The Catholic Truth Society, writing one of their pamphlets entitled “Why I left the Church of England”. He was invested (by the Pope) a Knight Commander of St Gregory. He died suddenly in 1924; on hearing of his death, Cardinal Bourne offered a requiem mass at Westminster Cathedral.; he was buried at Isleworth. A life-long bachelor, he left much of his estate to various Catholic charities.