More of a late 80s/very early 90s thing, they were written in the 60s but iirc weren't particularly well known or successful until Disney turned one of them into a terrible movie in 85.
Yeah, it occurred to me after the fact that these books are from the 60's, so people who grew up in the 70's and 80's might also know them. You're right that they didn't gain any major prominence until after the Disney movie though.
It's a damn crime that Black Cauldron in cartoon form is the only thing from this series to get any kind of screen adaptation ever. This could easily be five movies, maybe even five seasons of a show if paced out correctly (IIRC Books 3 and 4 are shorter while 2 and 5 are long and 1 is medium, so their lengths are all over the place).
Originally I think it was supposed to be a 3 book series, and the publisher wanted more or something, so Lloyd Alexander ended up adding books 3 and 4 to the story when he had already written some of the last book (which then became 5). Might explain the length differences, and why books 3 and 4 seem more like side-stories (really good ones). TBH Books 2 and 5 could probably be two seasons each to give us an even 7.
I don't know why I'm even talking about it though, not like it's happening. All things are possible though, lesser-known serieses than this have gotten adapted to shows over time.
Oh, and another issue: One of the two main characters, the girl, is a redhead. Her most defining characteristic, as a matter of fact, is her long "red-gold hair" and how it reflects her fiery personality. Lloyd Alexander was very specific about this.
...so Amazon or whoever would absolutely, 100%, cast her with someone who looks nothing like that.
