"What exactly constitutes a slasher? Definitions vary, but the core elements come down to a few things — one, the bulk of the film should unfold over a short time frame, like one night or a weekend; B, the film should focus on the victim pool and/or the killer while keeping police involvement to a minimum; and three, the events should take place in a relatively small geographical area like a campground, a big house, or a neighborhood. There's room for flexibility here, but a slasher should meet at least two of those three criteria. (That said, art is ultimately subjective!)
While the U.S. produces more slashers than every other country combined, those foreign lands haven't exactly been sitting idly on their hands. For this list we're looking at foreign slashers, films made outside of the U.S. that still bring the goods with their kills, killers, and set-pieces."