Trivia

This is the first animated Godzilla film, but not the first animated adaptation of the franchise. The first was an American animated series produced by Hanna-Barbera in 1978. A series of four educational OVAs titled Get Going! Godzilland that featured Godzilla and several other monsters were released in 1994 and 1996. Another American animated series, this time based on the 1998 American Godzilla film, ran from 1998 to 2000.

The monster cameos seen in the flashback montage mark the first time Dogora (from Dogora (1964)) and Dagahra (from Rebirth of Mothra II (1997)) have appeared in a Godzilla movie. The monster Orga also makes his first appearance in a film since Godzilla 2000 (1999). The Servum is a new kind of monster introduced in this film.

Originally envisioned as an anime series, but the success of Shin Godzilla (2016)'s Japanese theatrical release convinced the creators to combine the narrative into a trilogy of movies and put them into cinemas in Japan.

A prequel novel titled "Gojira Kaiju Mokushiroku" ("Godzilla: Monster Apocalypse") was released prior to the film's theatrical debut, on October 25, 2017. This detailed the monster attacks and humanity's futile fight against them that lead up to the movie's plot, and featured a huge variety of classic monster characters from Toho Studios' films. The events of the novel are referenced in the flashback seen in the beginning of the movie. These include:

• the giant mantis Kamacuras attacking New York
• the flying jellyfish-like monster Dogora wrecking London
• China creating a bio-weapon called Hedorah that kills Rodan and Anguirus, but then turns on China
• Daghara rampaging in Sidney
• Orga demolishing Ankara
• the Bilusaludo aliens creating MechaGodzilla to fight against Godzilla

According to the novel, most of the other monsters were destroyed either through humanity's efforts or by Godzilla.

As revealed by interviews published in late 2018, Toho specifically asked Polygon Pictures not to handle the anime trilogy as monster movies and to stay away from monster battles if possible. Their main intention was to bring in a new, mostly female crowd of moviegoers who would otherwise not be interested in monster films. Script writer Gen Urobuchi and director Hiroyuki Seshita are major monster film fans and wanted to stay close to Godzilla's roots, pit him against various other monsters and reference many of the classic films. Co-director Kôbun Shizuno, who never expressed interest in Godzilla, rejected these plans and proposed a new direction. He followed Toho's order to minimize the focus on the monsters, and even gave Godzilla a new type of energy blast ability, as he did not care for Godzilla's trademark ability to breathe radioactive fire.