The world has lost a true legend. George A. Romero, the man who was known as the Godfather of the zombie genre, has passed away at the age of 77. He died on Sunday in his sleep following a "brief but aggressive battle with lung cancer," as reported by his longtime producing partner, Peter Grunwald.

The L.A. Times was the first to break the news that George A. Romero has passed. According to their report, the horror icon died while listening to the score of one his favorite movies; 1952's The Quiet Man. His wife, Suzanne Desrocher Romero, and daughter, Tina Romero, were both at his side.

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George A. Romero broke truly new ground in the world of horror with his 1968 movie Night of the Living Dead, which he directed and co-wrote with John A. Russo. Not only did the movie essentially create the zombie flick as we know it, but Romero is given a lot of credit for casting a black actor in the lead at the time. His work paved the way for other directors like John Carpenter, Wes Craven and Tobe Hooper, who would have success in the years that followed. The Living Dead franchise continued throughout Romero's career, with 1978's Dawn of the Dead, which was given a remake in 2004 by director Zack Snyder. There is also 1985's Day of the Dead, 1990's Land of the Dead, 2007's Diary of the Dead and 2009's Survival of the Dead.

Outside of the zombie sub-genre, which he created, George A. Romero also made several other classic horror movies. 1973's The Crazies, which was also given a remake in 2010, is probably the best example of his great work outside of zombie horror. He also directed 1981's Knightriders. He was also given a writing credit on director Hèctor Hernández Vicens' Day of the Dead, which some of his characters appear in.

Prior to his passing, George A. Romero had been working on another entry in his Living Dead series, which he was set to produce. Road of the Dead, which was set to be directed by his frequent collaborator Matt Birman, is said to be a Mad Max meets Rollerball zombie movie where trained zombies race for the entertainment of the wealthy in Ben-Hur style Nascar races. Up to the end, he was still trying to reinvent the genre he created. There is no word yet on whether or not Road of the Dead will continue following Romero's passing.

In terms of all-time horror icons, George A. Romero will forever be right near the top and the void that is left behind following his passing is truly massive and we can't possibly expect for it to ever be filled. We send our thoughts to his friends and family and those in the horror and film community who are affected by his loss. RIP, George A. Romero.