[3]: 200 City State of the Invincible Overlord launched Judges Guild as a company, and was the centerpiece of Wilderlands of High Fantasy, the first licensed and published Dungeons & Dragons campaign setting.

[5] After ceasing publication, Judges Guild licensed a City State of the Invincible Overlord line to Mayfair Games from 1987 to 1989.

Other resources in the book included descriptions of notable inhabitants of the town, a table of random encounters, and a list of rumors that the gamemaster could incorporate into the game.

Bambra was disappointed by the contents compared to the original Judges Guild editions, saying, "Gone are the winding alleys and jumbled buildings, now replaced by a pretty but unconvincing suburban playground.

Buildings stand in their own spacious grounds, making the city look like nothing more than a sprawling village enclosed by stout stone walls.

Marsh also felt that the many tables that provided random monsters "that for some reason pop up in a back alley" was not enough to build an adventure with.

Marsh concluded, "The information that the referee is provided with isn't helpful and will require some tinkering to make the characters fit in with his own world, if he has one, or will just seem odd in terms of the City State campaign.

Nonetheless, Swan concluded with a positive recommendation, saying, "for referees in the market for this type of generic material, City State of the Invincible Overlord is a great buy".

[10] In his 2023 book Monsters, Aliens, and Holes in the Ground, RPG historian Stu Horvath noted, "the emphasis of the material is on making the city-state fun and interesting.