Luke Skywalker thought Ben Solo was the Chosen One before he turned to the Dark Side and became Kylo Ren. Although the nods have been subtle, the Star Wars sequels do still involve the maligned prequels. Indeed, right in The Force Awakens' opening scene Lor San Tekka talked about "balance in the Force", an idea first introduced in 1999's The Phantom Menace.
He is, of course, referencing the prophecy of the Chosen One which dominated George Lucas' original saga narrative; in Episodes I-III the Jedi bet the farm on Anakin Skywalker, which resulted in their near destruction before he was redeemed by son Luke and in doing so destroyed the Sith. However, Tekka's line and a new comment from Mark Hamill suggests that the ending of Return of the Jedi wasn't quite as tight as once suspected.
Speaking to Entertainment Weekly for their Star Wars: The Last Jedi coverage, Hamill discussed the fall to the Dark Side of his character's nephew and apprentice Kylo Ren, saying prior to the betrayal Luke thought Ben Solo was the Chosen One:
"[Luke] made a huge mistake in thinking that his nephew was the chosen one, so he invested everything he had in Kylo, much like Obi-Wan did with my character. And he is betrayed, with tragic consequences. Luke feels responsible for that. That’s the primary obstacle he has to rejoining the world and his place in the Jedi hierarchy, you know? It’s that guilt, that feeling that it’s his fault, that he didn’t detect the darkness in him until it was too late."
It appears that despite Vader killing the Emperor in Jedi, Luke still believed the Force out of balance and mistakenly thought Ben Solo - Anakin's grandson - was the key. This is a pretty big reveal, adding another layer to Kylo's betrayal - he didn't just destroy Luke's Academy, he undid his hope for the future - and shows that while he was able to redeem his father, Luke still repeated the same mistakes of the original Jedi. Fans have often questioned how the destruction of the Dark Side could infer balance, so it's certainly an interesting debate to explore.
The question now becomes who is the Chosen One in lieu of Kylo? The obvious candidate would be Rey, given how she's set up as the sequel trilogy's main hero, although it wouldn't be out of the question for Rian Johnson or Colin Trevorrow to pull a bigger turn in the next two movies and have something more complex.
Regardless, one thing it really does shows is that the prequels may still be important. The new Disney Star Wars movies have for the most part been rather slight in their acknowledgment of the movies - Rogue One's connections were more easter eggs than plot essential beats - but if we're going to have the Chosen One become a key element in the story again (something alluded to in this season of Star Wars Rebels), it's clear Episodes I-III are still an essential part of the mythos.
