JLA Watchtower was founded in 2004 and has been continuously operating from that time. Started by a group of superhero roleplayers from the so-called 'Nexus' communities on LiveJournal, Watchtower grew as a dedicated DC Universe roleplaying outlet.

The fictional universe of the JLA Watchtower game is much like the mainstream DCU - up to a point. Identity Crisis #1 is usually identified as the branch point - anything published in DC Comics after that hasn't necessarily been included, unless the players chose to adapt it on-screen. Events prior to that branch point are generally assumed to have happened, but we tend to be flexible on that point as well, if a player wants to adjust something when bringing in a character - provided it doesn't contradict anything we've referenced.