Picked up by AIP for American distribution, the 1964 sword-and-sandal pseudo-epic ROME AGAINST ROME (better known stateside as WAR OF THE ZOMBIES or NIGHT STAR--GODDESS OF ELECTRA) could technically be considered the first Italian zombie film, though it bears no resemblance to the gorefests of Lucio Fulci or Umberto Lenzi. No, this is an entry in the peplum film canon with a light sheen of the supernatural to set it apart from the other HERCULES-inspired rip-offs of the period.
Summarizing the plot is rather difficult--thanks to director Giuseppe Vari's sloth-like pacing, which makes it hard to follow the overwrought drama--but it has to do with two warring factions (one of which is led by John Drew Barrymore, as the obligatory esteemed actor gone a'slummin') in a fantasy setting passed off as ancient Rome. Barrymore, a high priest of some sort in cahoots with a three-eyed stone effigy of a goddess known as the Night Star, resurrects the bodies of their fallen comrades to send into the climactic battle--a sequence of gaudy, hyperlit color and slow motion action that some have deemed surreal but which really looks like cheap cinematic trickery.
Those into fantastic historical epics may want to give this a try, but there are much better movies that blend the horror and sword-and-sandal genres, like 1961's GOLIATH AND THE VAMPIRES. But for viewers more accustomed to the likes of GLADIATOR and 300, stay far away.