Greyhawk

During the era of Holmes Basic, the Greyhawk campaign setting was in a state of flux, transitioning from Gary Gygax's personal campaign to the first official campaign setting published by TSR.

The Foreword to the Holmes Basic rulebook (mid-1977) is a reprint, with minor editing, of the Foreword from the original D&D boxed set (1974), and contains a brief mention of the long-running "Greyhawk" campaign (as well as "Blackmoor"). The only other reference to the Greyhawk campaign is the spell Tenser's Floating Disc, which states "The wizard, Tenser, always greedy for more treasure, devised this spell" (page 15). This spell was devised by Gygax, who added a few new spells to the Holmes rulebook after receiving the manuscript from Holmes (see The Dragon #35, pg 13).

The novel Quag Keep by Andre Norton was published in early 1978, and excerpted in The Dragon #12 (Feb 1978), was set in Greyhawk, as envisioned by Norton using notes from Gygax.

In Nov 1978, the module B1 In Search of the Unknown was first published (and packaged in the 4th-6th prints of the Holmes Basic set), and contained the following advice: "In the mythical WORLD OF GREYHAWK (available from TSR) the stronghold can be considered within any one of the following lands - the Barony of Ratik, the Duchy of Tenh, or the Theocracy of the Pale" (pg 6). This preceded the first publication of the World of Greyhawk by almost two years, but it is likely that Gygax was working on it at the time, as the foreword to the WoG folio by Allen Hammack is dated Feb 1979. In an interview, Mike Carr mentions (see the B1 sourcebook, interview of Mike Carr by Geoffrey Mckinney).

The module B2 was first published in 1979 but doesn't contain any specific references to Greyhawk, although being written by Gygax it naturally has a Greyhawk feel.

The first published version of the World of Greyhawk setting finally appeared towards the end of the Holmes Basic-era (August 1980), as a folio.

Holmes himself