Haruo Nakajima, the actor who first portrayed Japanese movie monster Godzilla, has died aged 88. His daughter Sonoe confirmed his death to the Associated Press, saying that Nakajima had died of pneumonia after being hospitalised last month.

Donning the Godzilla costume for the first 12 films in the long-running series, the Japanese actor also appeared in Akira Kurosawa’s Seven Samurai and a number of Japanese war films.

Nakajima was born on 1 January 1929 in Yamagata, Japan. Contracted to Toho Studios, the actor first performed stunt roles in a number of samurai and war films, appearing as a pilot in a burning aeroplane in Eagle of the Pacific and a bandit in Seven Samurai.

Nakajima’s most famous work though came in the Godzilla films. His first appearance was in 1954’s Godzilla, for which he had to wear a 220-pound concrete bodysuit, due to a scarcity of rubber in post-war Japan. As well as being painfully heavy, the suit would become hot under the studio lights. “I stuck a thermometer inside the suit; 140 degrees,” Nakajima told CBS News in 2014.

To prepare for the role, Nakajima studied bears and elephants at the local zoo, as well as watching the original 1933 film King Kong. His adeptness at performing as Godzilla would lead him to star as the lizard monster in 11 sequels, with his final appearance coming in Godzilla vs Gigan in 1972.

Nakajima appeared in of other movie monsters, including Mothra in 1961 and King Kong in the 1967 Toho and Rankin/Bass co-production King Kong Escapes.

The Godzilla series was popular in a postwar Japan, which was still recovering from the atomic bombing of Hiroshima and Nagasaki nine years earlier. In the original film, Godzilla is created as a result of nuclear testing in the Pacific Ocean, and as such was seen as symbolic of the evils of nuclear war.

“Godzilla is a creature of the Americans,” Nakajima told CBS. “Godzilla’s breath is nuclear radiation. He showed our audiences that atomic bombs are frightening.”

While plenty of other actors have appeared as the monster in subsequent films, as well as the monster being rendered by computer animation, many fans believe that Nakajima’s was the definitive Godzilla. The actor agreed with that assertion, saying in 2014: “I am the original, the real thing,. My Godzilla was the best.”