Ernest Gary Gygax was an American writer and game designer best known for co-creating the pioneering role-playing game Dungeons & Dragons (D&D) with Dave Arneson. Gygax has been described as the father of D&D. In the 1960s, Gygax created an organization of wargaming clubs and founded the Gen Con gaming convention. In 1971, he helped develop Chainmail, a miniatures wargame based on medieval warfare. He co-founded the company Tactical Studies Rules (TSR, Inc.