So, this really has nothing to do with Greyhawk as Gary envisioned it.
I usually envision the western map edge of the Flanaess joined with the western edge of the Wilderlands, by means of a mystic ley line that reverses direction. If you walk through the desert you'll just end up infinitely retracing your steps unless you know when to turn back to reach one or the other place.
However, I've also always liked the idea that Greyhawk and Middle-earth share the same world, and the easiest solution for that is to stitch the eastern edge of Middle-earth against the western edge of the Flanaess.
The immediate ramification of doing that, of course, is that the Blue Wizards Alatar and Pallando now travelled east into the Flanaess and settled there—but as whom? Mordenkainen and Tenser? Or should they more on the order of deities?
Then there are the obvious Tolkien references in the 3 LBBs, and Mike Mornard has also pointed out a few times that the smaller 'giant types' were/are direct parallels to the Tolkien beasties: goblins = orcs of the Misty Mountains, orcs = orcs of Mordor, hobgoblins = uruk-hai of Saruman.
It's not much to go on, but hopefully others find the concept interesting enough to help ponder further ways to connect the two lands—either creatively or by pointing out things Gygax did himself that point to Tolkienisms, despite his vocal aversion to them.
Last Edit: Nov 18, 2019 0:30:59 GMT -6 by Starbeard