The film, Romero's sixth in the zombie franchise, is the first horror film in competition at the Lido since the festival's debut, when Rouben Maumolian's "Dr. Jekyll and Mr. Hyde" opened the 1932 edition, Venice artistic director Marco Mueller said.
In the movie, Romero's flesh-eating zombies are set against the backdrop of a warring world in which two feuding families disagree on how to dispose of the dead: One clan opts to kill them off indiscriminately while the other chains them up to "keep them among us." A band of AWOL soldiers arrive on Plum Island, off the eastern U.S. coast, hoping to find paradise but find that life there is all too similar to the war they left behind.
"Zombie films are always a vehicle to talk about something that happens in the present time," Romero told reporters. While no specific war inspired it, a host of current conflicts - from Northern Ireland to the Middle East - were all influences, Romero said.
"Discrimination, racial discrimination, religious discrimination and tribalism of any kind," he said. "I wasn't looking at Iraq and saying 'Oh, let's make a movie about that,"' he said.
"It's more about what's underlying man's inability to forget enmity," he said. "They're enemies even long after they've forgotten what started the conflict in the first place."
Some of Romero's previous "Dead" movies explored the Vietnam War, racism, consumerism, militarism and class differences.
Romero's 1968's classic "Night of the Living Dead" launched the franchise; he followed up with, among others, the 1979 "Dawn of the Living Dead" and the star-filled 2005 box office flop, "Land of the Dead."
"I don't know how many more there will be," Romero said. "It's a practical reality. I think I would prefer it if they were farther apart." But he said his financial backers frequently want him to do another if the latest one does well financially.
"I think if I were trying to make serious films about some of these topics I wouldn't be able to," he said. "So it's great to be able to bring the zombies and talk about social issues and have fun at the same time."