The Godzilla film series, a Japanese franchise, began in 1954. The name "Gojira" or "Godzilla" in Japanese is generally understood to be a portmanteau of gorira (gorilla) and kujira (whale), conveying the sense of a large, powerful creature. Notably, there are some in Japan who revere Godzilla as a kind of deity.
The second film in the series followed quickly in 1955. However, there was then an eight-year gap before the next film, in which Godzilla's appearance was slightly redesigned. A continuous set of films with various themes then followed until 1975.
After this, Godzilla's appearance was slightly changed again, and another set of films was released starting from 1985 and running until 2004. Notably, a non-Japanese film titled Godzilla, which did not feature the true Godzilla, was released in 1998. The original 50-year run of the Godzilla story concluded with Godzilla Final Wars in 2004, marking 29 films released over this period.
Godzilla's current appearance emerged after a 10-year hiatus with the film series that began in 2014. The narrative direction starting in 2014 takes the story in a very different direction. This was followed by three animated films in 2017 and 2018. The franchise has produced a total of 37 films up to the latest release, Godzilla Minus One, in late 2023.
In 2023, a TV series titled Monarch: Legacy of Monsters was also released. It is connected to the film series but follows a separate storyline and is not counted in the main film list. The final film in the current arc, Godzilla x Kong: The New Empire, is scheduled for release this year. Although it has been stated that this film will conclude the current story, we will have to wait and see what the production company decides to do next.
I believe the Japanese creators originally started the Godzilla concept as a way to explore the idea of genetic mutation—a change affecting humans due to the atomic bombs dropped on Japan, which then influenced animals, causing them to transform into dangerous creatures. This is because the first film clearly states this idea: that Godzilla was created by atomic activity. Furthermore, it appears that the scientific experiments happening around the world during various time periods have also contributed to changing the story in different ways. However, one consistent element the creators have maintained from the beginning is the concept that Godzilla absorbs radiation.