Sweetfires first came up with the idea of a Twine Wars while the early members were active on the SciFi Vine. At the time, it was suggested as a war on a single world - the crossworlding aspect came much later - and it was intended to take place on a storyboard, or linked storyboards, in the 'Castle' group at SFV.
After a lull in the conversation, the Great War idea was proposed as a completely new group at the SciFi Vine. Conversation and plans continued.
The SFV was showing signs of decrepitude and after one mammoth chat it was decided to create the group with a different provider.
Pro continued happily as an Excite Group until they changed their services and no longer offered free message board hosting.
It was in the latter days of Excite that the crossworlding aspect was introduced. Since the group started, several of the members had got interested in amateur worldbuilding and wanted their creations to be part of the Great War.
The webhosts were never reliable, and one major failure resulted in several months' worth of data being lost. A hasty relocation was in order. (The offending host is called Xeran.)
Mutt rescued all available data and got the Pro boards up and running on des own domain. Thus did the group reach HHnet, where it currently resides. The name was changed to Profusion. The management has changed, but much of the original membership remains (or still drops by to say hi).
In March 2005, and again in September 2005, Mutt's webhosting service decided it wanted to start losing Profusion's data (such that any posts made in a day would start disappearing overnight). (Because of its awful customer service since the company was bought out, and complete lack of aftercare or compensation for the loss of data, we are naming and shaming the host as Easyspace.)
Mutt switched to a new host as soon as des paid-up period with the rubbish one ran out in May 2006. After some testing, Pro reopened on 11 June 2006. It's been up ever since. (Shout-outs to UnitedHosting and their superb support.)
Plans to get Pro its own spiffy domain are currently on the back burner. If membership picks up and we get the War moving, you never know.