Disney's Halloween Treat, on CBS
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This first aired in 1982 as an episode of The Wonderful World of Disney. There were apparently a couple of other Halloween specials, in 1981 and 1983, both called "A Disney Halloween", and I must have seen at least one of those in addition to "Disney's Halloween Treat", but this is the title I remember best, and the one I find most nostalgic. And I wouldn't be able to remember what clips I saw in each of the three specials. Luckily, we have the internet for that, but I feel like I've read contradictory things about all this on various websites, over the years since I started this entry. In any event, some form of Disney Halloween special aired throughout the 80s and into the 90s, regardless of what name it went by or what clips it included.
Whatever. "Halloween Treat" was hosted by a Jack-o-Lantern puppet thing, while "A Disney Halloween" was hosted by the Magic Mirror from Snow White. Both specials included clips from various old Disney movies and short films. Some of those things didn't really have anything to do with Halloween, but were just included because Disney villains are supposed to be scary. Some of the clips definitely were Halloweenish, though. Here's what Wikipedia currently says about each special:
1981: The Headless Horseman, the Evil Queen from "Snow White and the Seven Dwarfs", Trick or Treat, Maleficent from Sleeping Beauty, and Lonesome Ghosts.
1982: Opening and closing credits included at least part of The Skeleton Dance. Madam Mim from "The Sword in the Stone", Night on Bald Mountain from "Fantasia", Captain Hook from Peter Pan, Cruella de Vil from 101 Dalmatians, the Evil Queen from "Snow White" again, Si and Am from Lady and the Tramp, the Headless Horseman again, and a few other short films.
1983: This was on Disney Channel, which I didn't get, and I'm not sure whether or not I saw it on "The Wonderful World of Disney" on a channel I did get. It included clips from both the 1982 special and a 1977 special that I doubt I could have ever seen, or certainly wouldn't remember, being only 2 years old at the time. It was hosted by both a narrator and the Magic Mirror, as in the 1981 special. Clips included "Night on Bald Mountain", Madam Mim, The Old Mill, "Heffalumps and Woozles" from Winnie the Pooh (something I've always associated with Halloween, so maybe I did see this special), "Lonesome Ghosts" and "Trick or Treat" again, and various other stuff.