He pioneered or developed several aspects of the hobby on his HO scale Gorre & Daphetid model railroad in Monterey, California, popularizing them with numerous magazine articles and photographs starting in the 1940s.
In addition to his superdetailing of locomotives, rolling stock, structures, and scenery, Allen was known for populating his model world with scale figures in humorous scenes.
Other techniques Allen promoted were realistic train operation and the use of forced perspective to create the illusion of a model railroad layout larger than it really was.
Born in Joplin, Missouri, Allen lost his father to typhoid fever when he was three; his mother died during the flu epidemic about nine years later.
After completing high school, Allen attended UCLA, and joined the Reserve Officers' Training Corps (ROTC).
In 1935, John's paternal grandparents died, leaving him about $1,900 ($42,224 today[1]), then the equivalent of a year's salary for a middle-class man.
After completing school, John and another student opened a photography business in the Westlake Park area of Los Angeles.
Before World War II, Allen and his brother Andrew visited an uncle living near Oakland who had a model railroad.
He opened a new photography shop on the main street with partner Weston Booth, and did a brisk business photographing servicemen.
Wrote Westcott: "It aroused comment because John had modeled pigeons and their evidences along the ridge of the roof.
Pigeons and other animate detail, once considered un-acceptable in this hobby, were given another look; and many a modeler began to humanize his railroad.
This caused a fire, investigators later determined, according to Linn Westcott's book Model Railroading with John Allen.
The fire was quickly reported and extinguished fast enough to save the house, but it destroyed the final, still-unfinished incarnation of Allen's railroad.
The first wide public mention of Allen's death was an obituary penned by editor Tony Koester in the March 1973 issue of Railroad Model Craftsman.
[3] "John Allen was an institution, Although his material had appeared in print on countless occasions (the December 1947 issue of Railroad Model Craftsman featured a John Allen cover), reader enthusiasm for his well known HO scale Gorre & Daphetid never wore down," Koester wrote.
"[3] The April 1973 issue of Model Railroader magazine contained an obituary by editor Linn Westcott and a cover photo of Allen.
There is a video about John Allen's railroad by Sunday River Productions called The Gorre & Daphetid[7] with footage shot by Richard Reynolds with a small intro by Glenn Beier who also operated on the G&D.