Earlier an image was leaked of Golden Age which hinted at that a new Assassin’s Creed game was in development at Ubisoft codenamed Golden Age.
Assassin’s Creed Unity was the first next-gen game from Ubisoft and it looked like it was going to be a successor to that. However, Ubisoft have clarified that Golden Age is in fact the codename for Assassin’s Creed: Black Flag which was released in 2013.
“Before we officially announce a game to the world, we use a working title or code name to refer to a project internally. Assassin’s Creed Golden Age was the internal name given to Assassin’s Creed Black Flag. It is not the name of any future Assassin’s Creed title.”
The image that was leaked can be found above.