James Edgar was born Thomas Eric Edgar on 1908 in Newton-le-Willows. He started out writing radio plays, including Murder Case (1953) and The Fielding Case (1956) on the BBC Home Service's Saturday Night Theatre, and short stories, before Peter O'Donnell advised him to take up writing comic strips.
He started writing the western strip Matt Marriott, drawn by Tony Weare, for the London Evening News in 1955, which continued until 1977. Other westerns he wrote include "Rusty Flynn - Rodeo Roughrider" in Tiger from December 1956 to April 1957, and George Stokes' Wes Slade in the Sunday Express, which he took over writing from Stokes, being credited as writer from 1979 until it was taken over by writer-artist Harry Bishop in 1980. Edgar is also apparently credited with writing Bishop's Gun Law in the Daily Express.
He wrote scripts for Fleetway's war libraries in 1962-65, contributed to the Eagle and Boys' World, and took over writing the Daily Mirror's science fiction strip Garth from O'Donnell in April 1966, writing it regularly until September 1985, and occasionally after that until 1992. He may have written scripts for Jack Monk's Buck Ryan in the Mirror and David Wright's Carol Day in the Daily Mail, although this is unconfirmed.
He lived in Kettering in Northamptonshire, and regularly socialised with Frank Bellamy and his wife Nancy. After the death of his wife Jessie in 1994 he went to live in a residential home in Sleights, Whitby where he died on 4th July 1998.
- Steve Holland, Jim Edgar, Bear Alley, 16 September 2006
- --, George Stokes - Wes Slade, Bear Alley, 27 July 2008
- --, Eagle Authors, Bear Alley, 19 April 2008
- --, Boys' World Artists and Authors, Bear Alley, 8 April 2009
- Domingos Isabelinho, Monthly Stumblings # 18: James Edgar, Tony Weare, Hooded Utilitarian, 30 October 2012