In 1971, WRG published Armies of the Macedonian and Punic War by Phil Barker - the first in a ground-breaking series of books aimed at wargamers, and attempting to translate the latest research into clear and reliable reconstructions of the soldiers of the ancient world. Barker's next in the series, Armies and Enemies of Imperial Rome, went through four editions over ten years and is widely recognized as a definitive guide to the appearance of the Roman Army. For many enthusiasts, the modern approach to historical wargaming in these periods began with Phil Barker's unique contributions.
In recognition of his immense contribution - through stand-alone publications, WRG rules and Slingshot articles - The Society of Ancients has named its new award for outstanding contributions to Slingshot in the period 500 BC to 1 AD The Phil Barker Prize.
For a brief appraisal of Phil Barker's contribution to wargaming, there is a Wikipedia entry here.