Hi Outlaw, and hi to everyone else too. I'm new here, but I've been lurking for a while.
Let me try to answer. The first (A)D&D product to describe the World of Greyhawk was the World of Greyhawk folio from 1980 (or possibly 1979). This setting was later expanded in the 1983 World of Greyhawk boxed set. Both were written by Gary Gygax and both described the world as of the year CY 576. This setting was the 'home' of the 1st edition AD&D game, and was the place where most 1st edition adventure modules (including all of the classics) were set. Most of the elements of the 'standard' D&D milieu (eg. races, monsters, magic spells and items, cosmology, etc.) originated in this setting.
After Gygax and TSR separated in 1985-86, the management at TSR dramatically cut down on the output of new Greyhawk material. The last 1st-edition module for Greyhawk (and the only one published after Gygax' departure), WG7 Castle Greyhawk, was a parody. When the 2nd edition of AD&D was published, TSR took some steps to revive the setting. First, they published the City of Greyhawk boxed set which described the city of Greyhawk as of CY 582. Then they introduced Vecna to the Greyhawk setting. Then David Cook wrote the Greyhawk Wars, which took place in CY 582-584. Finally, Carl Sargent wrote the From the Ashes boxed set, which descibed the post-war World of Greyhawk as of CY 585, and updated to the 2nd edition AD&D rules. Several related supplements followed. TSR stopped publishing any Greyhawk materials after 1993.
In 1998, TSR - now owned by WotC - revived the setting. The Players Guide to Greyhawk by Anne Brown and The Adventure Begins described the setting as of CY 591, and several related accessories and adventures followed.
The Living Greyhawk Gazeteer, published by WotC in 2000, describes the setting as of the year CY 591 and updates it for the 3rd edition D&D game.
For your specific questions,
1. The Scarlet Brotherhood was a very mysterious group in the original set. It was obvious that they were up to something no good, and that it was something big. It just wasn't specified. Products that have been published since then reveal what they were up to and just how big it was.
2. Of course the Greyhawk Wars were fabricated! The world is fictional, so naturally everything that happens in it is fabricated. I don't think that the political restructuring was the goal of the designers who wrote the war, just a consequence. I think the designers' goal was to make the setting dynamic and to make new products.
3. The Great Kingdom fell after the Greyhawk Wars.
4. Dyvers has been independent of Furyondy for a long time. It was independent in all published versions of Greyhawk.
5. The Baklunish-Suel wars took place a looong time ago, and yes the wars did destroy their lands. This was ancient history even in the original folio.
In summary, the main difference between 'new' Greyhawk and 'old' Greyhawk is that a lot of time (15 game-world years, 20 real-world years) has passed since the 'old' Greyhawk was published, and that that the 'new' elements of the setting were designed by people other than Gary Gygax.
-Aximander
