Dawn of the Dead (2004) might be a prequel of sorts to Army of the Dead (2021). There is no character overlap. It’s unclear if the zombie outbreak in Las Vegas in Army of the Dead ever made it the rest of the world.
Dawn of the Dead marked Zach Snyder‘s first major film debut as a director, and was a remake of George Romero’s 1978 film.
The movie details the first days of the zombie outbreak in the suburbs of Milwaukee, Wisconsin and the band of survivors trying to make their way to safety.
Screen Rant: Snyder Clarifies Army of the Dead Not a Sequel to Dawn of the Dead