Greyhawk, also known as the
World of Greyhawk, is a fictional world designed as a
campaign setting for the
Dungeons & Dragons fantasy roleplaying game. Although not the first campaign world developed for
Dungeons & Dragons—
Dave Arneson's
Blackmoor campaign predates it by a few months—the world of Greyhawk was the setting most closely identified with the development of the game from 1972 until 2008. The world itself started as a simple dungeon under a castle designed by
Gary Gygax for the amusement of his children and friends, but it rapidly expanded to include not only a complex multi-layered dungeon environment, but also the nearby city of Greyhawk, and eventually an entire world. In addition to the campaign world, which was published in several editions over twenty years, Greyhawk was also used as the setting for many adventures published in support of the game, as well as for
RPGA's massively shared
Living Greyhawk campaign from 2000–2008.