Well my group and I will be starting up a new C&C campaign, and the funny thing is...this is the only game where all of us feel comfortable enough to take turns running.  Now don't get me wrong, this is a great thing, as normally I never get to play...but last time we tried it, there were hiccups.  Most of this was due to the fact that everyone wanting to run kinda arose spontaneously and without us thinking about it beforehand.  So this time I decided to come up with a "campaign world" that would facilitate more than one GM.

So, my major concerns were as follows...

1.)Space...The world should have enouigh space for different GM's to make certain parts "their own".

2.) Vagueness w/a hook...I also wanted the world to be vague enough to accomodate differing playstyles, while still having a hook to tie everything together.

3.) Freedom...Kind of ties into vagueness, but more focused on the ability to put anything in the world without it feeling forced.

4.) One shots or storylines...I will probably be running the most adventures out of my group of five, so I would like to have a "storyline" so to speak...but I also want this world open for one shots and, if they want, my other players to have overarching plots as well.

Anyway, this is what I came up with...

A world shattered by some dimly, if at all, remebered cataclysm.  It is now a collection of "islands" held together by ley lines of magical energy.  Sort of like an enormous spider web(in the shape of a sphere around the worlds core) with flecks of dirt scattered across it.  The only way to reach different islands is by way of Lineships...specially made ships that use hot air ballons to float and mana anchors to keep them attached to the ley lines.  Most of the cultures in the world are isolated, and very little of the "web" has been mapped.

I was thinking this world could allow for a great amount of freedom as far as character creation(we will be using the base classes, netbook of classes, and multi-classing rules)  as well as background(they can create their own "home island" if they want}while still allowing us to slowly fill in the "web" as different people take turns running adventures, without actually stepping on each others toes.  The history could also slowly be discovered, and a collaborative effort on everyone's part.

So any suggestions for improving this concept or even for facilitating a campaign with multiple GM's would be greatly appreciated.

Honestly, most published settings for D&D (e.g., Mystara, Aber-Toril, etc) meet all of your criteria. Me, I'd go with the AD&D 1e boxed set for Aber-Toril (i.e., Forgotten Realms) and some of the early supplements (e.g., Dreams of the Red Wizards, etc). This fills in the world's basics, though since it precedes the Time of Troubles (which was, IMO, a bullshit marketing device) and the restraining canon that followed, it leaves GMs a great deal of space to do with as they will. Plus, all of that 1e material will be a cinch to convert to C&C.

I got this same suggestion on rpg.net, so I'm seriously considering it.  May have some time, since we've been talking about running a few sessions of Qin:The Warring States before starting the C&C campaign.  Thanks for the suggestion, I think I will look into some of the older AD&D settings...I was particularly interested in Planescape, as it sounds almost perfect for what I want.

Quote from: Ghost_FaceI got this same suggestion on rpg.net, so I'm seriously considering it.  May have some time, since we've been talking about running a few sessions of Qin:The Warring States before starting the C&C campaign.  Thanks for the suggestion, I think I will look into some of the older AD&D settings...I was particularly interested in Planescape, as it sounds almost perfect for what I want.

Planescape may work, though the setting itself has a very rigid cosmology. It would be a great secondary setting for you, I think. It was designed to bridge different Prime Material worlds together and, in that regard, you may find it useful. That said, in and of itself, I think that it lacks the kind of "open space" for independent development that you seem to want.

It seems like you've prepped it extremely well, meaning you've built the skeleton.  You'll need to agree on what the characters do in the campaign.  Are you playing the same characters or is each GM running for a different cast of characters?  Make sure the setting and style are easily grasped by the other players so the skeleton can be fleshed out with some continuity.  If you're playing the same characters, you'll need to develop ways to transition to the next GM without overly constraining GM preparation.  You also need to figure out what to do with the GM's character.  If each GM is running for different characters, you need to develop somewhat of a timeline to determine when something is taking place in the campaign and how each scenario impacts the setting.  

I think if you don't overly detail the setting at first, you'll make an excellent platform for multiple GMs to expand on.  I take it your first adventures will be setting the mood and style of the campaign?