By the late 1960s the miniature wargaming hobby had grown large enough that there was a demand for rulebooks dedicated to a single historical period.
[1] A few years later the Wargames Research Group began producing rulesets with an emphasis on historical accuracy.
[5] The series came to include games and books by Lou Zocchi, Tom Wham, and Dave Arneson.
[4]: 6 Other notable titles in the series are Tractics, one of the first published games to make use of the 20-sided die, and Don't Give Up The Ship!, the first collaboration between Gygax and Arneson, the co-creators of Dungeons & Dragons.
Lowry apparently failed to recognize the potential of Dungeons & Dragons,[6] prompting Gygax to found TSR.
In addition to Gygax and Arneson, Lowry worked with Lou Zocchi, Tom Wham, and Mike Carr.
[citation needed] In 1973 the Guidon Games imprint was shut down by its parent company, Lowry Hobbies.