Moore had originally pitched two potential prequels IIRC, minutemen and I'm digging into the back of my memory... I want to say Rorschach and Mothman?
It never got past the germs because of Moore's falling out with Dc, however, there was plenty of information to build the prequels on top of because of Moore's participation and consultation around the Watchmen RPG. Even if you don't play RPG's, much of the Moore approved back story is very interesting to watchmen fans.
DC HEROES WATCHMEN SOURCEBOOK MAYFAIR RPG | eBay

DC HEROES WATCHMEN TAKING OUT THE TRASH MAYFAIR RPG | eBay

DC HEROES WHO WATCHES THE WATCHMEN MAYFAIR RPG MODULE | eBay
It never got past the germs because of Moore's falling out with Dc, however, there was plenty of information to build the prequels on top of because of Moore's participation and consultation around the Watchmen RPG. Even if you don't play RPG's, much of the Moore approved back story is very interesting to watchmen fans.
DC HEROES WATCHMEN SOURCEBOOK MAYFAIR RPG | eBay
DC HEROES WATCHMEN TAKING OUT THE TRASH MAYFAIR RPG | eBay
DC HEROES WHO WATCHES THE WATCHMEN MAYFAIR RPG MODULE | eBay
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