The Tolkien estate can veto pretty much anything in Amazon's Lord Of The Rings
Anyone hoping for some kind of clever revisionist take on Middle-Earth history in Amazon’s upcoming Lord Of The Rings prequel series is probably going to be disappointed, as Engadget is reporting that Tolkien scholar Tom Shippey is on board as a consultant to ensure on behalf of the Tolkien estate that “the main shape of the Second Age is not altered.” In other words, the established canon that J.R.R. Tolkien established in his books cannot be altered by anything that Amazon does, and the estate “maintains power of veto” on “any content” Amazon has in mind. On top of that, the First and Third Ages of Middle-Earth history are completely “off-limits” for the TV show—meaning you won’t see any familiar stuff from, say, a series Peter Jackson movies, because that’s all from the Third Age.
What Amazon can do, is fill in gaps that don’t disrupt the main canon, sort of like a very expensive TV series that is all Solo: A Star Wars Story. As Shippey explains, the Second Age is all about Sauron trying to reform Middle-Earth in a nice way but then gradually succumbing to the temptations of evil. Or, in Tolkien terms: “Sauron invades Eriador, is forced back by a Númenorean expedition, returns to Númenor. There he corrupts the Númenoreans and seduces them to break the ban of the Valar.”
All of that will presumably make sense once we’ve seen Amazon’s show, or if you’re a Tolkien scholar like Tom Shippey.