What we need, part 1: We need a register of nations which will be involved. This needs to be publically posted. Each nation should have some designated player which runs point for it.
Why we need that: We need to understand who is participating (for part 2), and we need to understand who can "speak" for that nation as we coordinate this RP.
What we need, part 2: We need an overarching outline made which incorporates the general roles of each nation and timing of events. This won't dictate RP on a post-by-post basis, but it will highlight generally important events, the way the war begins and ends, etc.
Why we need that: This will ensure everyone knows in general and beforehand what to expect the outcome of the war to be, and nobody ends up rage quitting because somebody shoots (to steal Doc's phrase, which basically means somebody goes way off base and makes a move nobody likes). This will also allow us to make sure we involve everyone meaningfully.
What we need, part 3: In accordance with rule 21.3:
23.1 Role-play events between nations, such as wars, will be officially recognised if before they are commenced, in all of the concerned nations a RP event bill outlining the event is approved by a 2/3rds majority of all players with seats (not just those with seats who vote) and over 50% of the seats in the legislature. This bill must specify the necessary and possible consequences of the role-play event, as well as a clause that deals with the eventuality of one or more players becoming absent for more than a specified time, and how such an absence is to be interpreted in in-game terms.
In every nation that will be participating, we need an identical RP Event bill proposed and properly passed. (The RP Team will probably create a sort of template for this?)
Based upon the Nations participating and the diplomatic alignment of said nations, we will be able to determine sides (or at least the war leader/s of the opposing sides)
List of Nations Participating