My Personal History with D&D
That first campaign was a short-lived homebrew, which was quickly replaced by a Greyhawk campaign using Sunless Citadel and Return to the Temple of Elemental Evil. We played that campaign for a couple of years until we hit a total party kill (TPK) and the DM decided to simply end it there.
What was lacking was something of a mix between the FR Campaign Setting, the 32-page D&D Gazetteer, and the Living Greyhawk Gazetteer. Essentially, Greyhawk needed a 3e player's guide with feats, races, prestige classes, and snippets of history easily digestible by those who are new to the setting. Without such a book, I had a hard time immersing the players in the politics and cultures of the world.
Eventually, we all got burned out on Greyhawk. That's when I proposed that we explore WotC's first original campaign setting, Eberron.