Another arguable entry into the horror genre that I would defend as at least a solid thriller. Dustin Hoffman and his hot wife move back into her home town in England. The locals all see Hoffman as a real wuss and decide to just take his wife whenever they want her. This leads to some very distressing situations as Hoffman must find his inner badass and protect his wife. The "others" in this movie happen to be English working class types but the real real horror element (to me) comes from bullies driving otherwise rational people to irrational places. I would argue that is the central theme to Last House on the Left, and everyone agrees that is horror.
Anyway, this movie is directed by old Sam "Blood N Guts" Peckinpah with lots of unsettling edits and shot compositions. Of course, this is a very violent movie and not for everyone but I would highly recommend it if you like home invasion thrillers like the original Purge.