Great Campaigns of the American Civil War is an unusual example of a game system started by one designer that's been almost wholly taken over by a player-fan who has become the de facto lead designer in the series.
Joe Balkoski started the series with Stonewall Jackson's Way in 1992 by publisher Avalon Hill. As conceived of by Balskoski SJW is a full-bore, 1/2-inch counter, small-hexed, chart-heavy, scenario-laden, tweezers-needing wargame untouched by any euro-ized elements.
During the design process it became clear it would be useful to divide the project in two, spawning Here Come the Rebels as an automatic sequel and starting a hoped-for series. HCR appeared in 1993, followed within the year by Roads To Gettysburg (which made some key rule changes that were eventually abandoned and required a new set of counters later.) RTG made the series "official" to the public, with box art christening it "Vol. III" in the "Great Campaigns of the American Civil War."
Two years later in 1995 Vol. IV appeared, the ambitious Stonewall in the Valley which was a very long game coverin all of Stonewall Jackson's Valley campaign. Up until this point the project was entirely in Balkoski's hands, but player Ed Beach was already working on Stonewall's Last Battle (Vol. V) about the classic Chancellorsville campaign, which appeared in 1996.
Balkoski and Beach collaborated in the sixth game in the series, On To Richmond, which was another lengthy game showing the entire Peninsular Campaign, published in 1998. It turned out this was the last of the series under the old Avalon Hill, as the company was sold just a few months later.
Hardly a beat was missed, however, as the series was one of the first picked by Curt Schilling's Multi-man Publishing (Of ASL fame) with the 1999 publication of The Skirmisher No. 1, edited by Beach and Balkoski. This featured a set of "Standard Rules" that regularized things over the series and included new counters for RTG to bring it in compliance with the series standards. The magazine doesn't say, but internal evidence in the form of standard artwork and the overall look imply that the Skirmisher was designed using artwork from the old AH art design staff.
In 2001 Grant Takes Command was published by MMP, and this, too, credited Beach as the sole designer, making the transition nearly complete. Beach mentions that Balkoski (who was staking out a career as a writer of popular history) didn't have much time for the project, providing some overall guidance.
The appearance of Skirmisher No. 2, in 2003 from MMP showed that the GCACW was completing the tranistion from one designer's baby to a more fan-supported approach. While Beach was the overall editor, most of the new content, including two full-sized game scenarios (Rebels in the White House and Burnside Takes Command) by teams of new designers. These new scenarios could easily have been stand-alone games as they have their own unique counter sets, but because their action takes place on existing maps and could take advantage of the standard rules and common market sets they could appear in this less-expensive format. They really are, however, functionally new games in the series. Perhaps they could be considered volumes VIIb and pre-V.
It's interesting to see how Beach was able to move into the lead design slot so seamlessly. The essence of the Balkoski design has been retained throughout and it's hard to pick out any obvious changes by Beach, especially because the entire series has turned into a very collaborative affair over the years with many changes incorporated from playtester and player input.
With the exception of the First Bull Run campaign, which will probably appear as another Skirmisher--style module at some point. the entire Eastern Theater is covered by the series, so the next one is supposed to be in the Western Theater, although the sedate publishing schedule of MMP means it's hard to know when that may happen.
It's an automatic buy as far as I'm concerned, though, whenever that may be.