The film takes place in 2026.
The orangutan that is featured prominently in the film is named Maurice. This is a reference to Maurice Evans, who portrayed the orangutan Dr. Zaius in Planet der Affen (1968) and Rückkehr zum Planet der Affen (1970).
According to Director Matt Reeves, the original draft of the screenplay, which was written before he was hired, was set further in the future, with the apes having obtained the ability to speak almost flawlessly, and Caesar playing a much smaller role. Reeves thought it would be more interesting to explore Caesar's story at an earlier stage, and asked for permission to re-write the script from scratch. His request was granted, on the condition that he deliver the film in time for the scheduled release date.
Despite having a cameo via video tape, James Franco had no involvement nor knowledge of his cameo. The video is stock footage from Planet der Affen: Prevolution (2011). In an interview Franco stated, "Wait, I have a cameo? I didn't even know that. You know, I don't even think they asked my permission to do that."