Robert Lionel Fanthorpe cowrote with his wife Patricia Fanthorpe. Pseudonyms: Erle Barton, Lee Barton, Thornton Bell, Leo Brett, Bron Fane, R.L. Fanthorpe, R. Lionel Fanthorpe, L.P. Kenton, Victor La Salle, Robert Lionel, John E. Muller, Phil Nobel, Lionel Roberts, Deutero Spartacus, Neil Thanet, Trebor Thorpe, Pel Torro, Olaf Trent, Karl Zeigfreid

The Reverend Robert Lionel Fanthorpe is a priest and entertainer, and has at various times worked as a journalist, teacher, television presenter, author and lecturer.

Born in Dereham, Norfolk (UK), his parents were shopkeeper and teacher, Greta Christine, née Garbutt. In 1957 he married Patricia Alice Tooke, with whom he has two daughters (born 1964 and 1966). From 1958 to 1962 he was a teacher at Dereham Secondary Modern School, then from 1961 to 1963 he studied Education and Theology at Keswick College, Norwich, and was then again a teacher at Dereham until 1967, after which he served in the British Army and was a tutor at the Gamlingay Village College in Gamlingay, Cambridgeshire, and course leader with the Phoenix Timber Company in Rainham from 1969 to 1972 . From 1972 to 1979 he was Headmaster at Hellesdon High School in Norfolk. In 1974 he acquired a bachelor's degree at the Open University. The marriage currently live in Roath, Cardiff, South Wales.

In the early 1950s, Fanthorpe began writing short stories that appeared in various magazines published by John Spencer & Co., such as Futuristic Science Stories and Worlds of Fantasy. From 1954, Fanthorpe's novels appeared primarily in the Badger Books series of the same publisher. In the good decade between 1954 and 1967, Fanthorpe was astonishingly productive. Under various pseudonyms, some personal and some publisher pseudonyms such as Victor La Salle, John E. Muller and Karl Zeigfreid, Fanthorpe wrote much of the supernatural tales and science fiction published in the Badger Books, a total of well over 100 novels and countless short stories. At times a 45,000-word novel was published every 12 days at a flat rate of £22.50, with Fanthorpe dictating his lyrics on tape and then having friends and family transcribe them, after a quick proofreading of the text then going to the publishers. The production method caused frequent careless mistakes, inconsistencies and plot gaps, and the story often came to an abrupt end because he did not have an exact overview of the extent of the text produced while dictating it. Despite such shortcomings, it is conceded that his products often need not fear comparison with the works of other prolific writers. In particular, some stories from the series about Val Stearman, an adventurer in the style of Bulldog Drummond and the mysterious immortal La Noire are considered highlights of Fanthorpe's work. A contributing factor to the large number of pseudonyms used was that the Badger Books series often included so-called magazine volumes, i.e. collections of stories allegedly by different authors. In fact, the stories in such a volume came all or mostly from Fanthorpe under various pseudonyms.

From the early 1980s, together with his wife, he signed a series of non-fiction books on historical mysteries, for example on the legend of the Templars and on Rennes-le-Château, as well as on themes of anomalistics and cryptozoology. Adept at such subjects, he has appeared on television on a number of occasions, notably as presenter and writer on the British television series Fortean TV (1997) and Forbidden History (2013–2016).