HBO killed one Game of Thrones prequel and formally announced a different one all on the same day. Which is hilarious because our news cycle is just nuts these days. But it's also very interesting, business wise and creatively. The show that is NOT going forward would have been set a few thousand years before GOT, with the early Starks and a bunch of old families fighting the White Walkers (the first time). And this actually had a pilot episode shot (so it must have missed the mark).
The show that IS going forward will be called House of the Dragon. And, personally, I'm way more excited about this idea (even though they’ve made none of it yet). It'll be set 300 years before GOT, and it's all about the Targaryen dynasty. Keeps it closer to the stuff we know. Allows you to evoke the spirit of the original show more. Makes sense all around.
The show will be based on George R.R. Martin's book, Fire & Blood. Check out the official announcement tweet below for more information on the creative team: