As mentioned, Legend was the prelude and inspiration for the most influential piece of zombie culture ever, Romero's Night of the Living Dead in 1968. While it wasn't the first (there was White Zombie in 1932 and I Walked with a Zombie in 1943), when you say "zombie movie" to most people, Romero's classic is probably the first image that comes to mind. And if it isn't, they're probably thinking of an image inspired by Romero's classic. Made on a small budget in a Pennsylvania farmhouse, Living Dead was a scathing critique of Vietnam-era America and a damn scary movie all at the same time. It proved that horror didn't have to be just about jumps and thrills, that you could actually make social commentary through the tears of fear. The word "zombie" is never actually used in Night of the Living Dead (although Romero would embrace it in his later Dead films), but it would still influence the genre more than any film before or ever since.
Romero would go on to direct four more Dead films, including Dawn of the Dead, Day of the Dead, Land of the Dead and Diary of the Dead. Over the years, his films have inspired numerous remakes (two for Night, one for Dawn and one for Day) and a half-dozen sequels. The Dead movies are the Yankees of zombie culture -- never going away and occasionally ending up as world champions. As much as Night critiqued late-'60s values, the original Dawn of the Dead, arguably the best zombie movie ever made, was a strong commentary on American consumerism, with Day of the Dead functioning as Romero's commentary on the military complex of the '80s. Although it wasn't completely about zombies, Danny Boyle's 28 Days Later was clearly influenced by the original Dead trilogy. In fact, the entire arc of 28 Days Later can be successfully grafted onto the Dead trilogy, with the first act of 28 Days reflecting the isolationism of Night, the second act of moving to the city reflecting the cultural commentary of Dawn, and the final act of Days focusing on military action just like Day of the Dead.
