While the Star Wars prequel trilogy isn't regarded with the same reverence as the original Star Wars movies by many fans, there's no questioning that they're integral to the mythology set in that galaxy far, far away. That time period was expanded upon in the Star Wars: The Clone Wars animated series, and it's still referenced or revisited in books, comics and video games. However, because The Force Awakens, the first installment of the new cinematic Star Wars trilogy, is set 30 years after Return of the Jedi, there were more callbacks to the Original Trilogy. However, Star Wars: Episode IX director J.J. Abrams and screenwriter Chris Terrio have suggested that the 2019 Star Wars installment will somehow tie into the tale that was told across The Phantom Menace, Attack of the Clones and Revenge of the Sith.
Reddit user 114D recently met J.J. Abrams and Chris Terrio (and has the picture to prove it), and supposedly during their conversation, the two men said that Episode IX "unites all three trilogies and brings everything together." When 114D mentioned that the Prequel Trilogy was his entry point into Star Wars franchise, Terrio said that there will be Prequel elements in Episode IX, although he didn't elaborate on what they would be. Terrio also said that Episode IX's story would make it feel like all these movies are all happening in the same universe, in case the lightsabers, blasters and cool vehicles aren't enough for you.
By the time of The Force Awakens, it's been more than 50 years since the events of Revenge of the Sith, so for many, the time of the Old Republic and the Jedi Order is the stuff of history and legend. Given the presence of characters like Luke Skywalker and Leia Organa, as well as The First Order directly rising from the ashes of The Empire, it's no surprise that the current Star Wars sequel trilogy is more closely tied to the Original Trilogy. Still, assuming this information is legitimate, the idea that Episode IX will include important connections to the Prequel Trilogy does sound fascinating. Though keep in mind that something could change down the line in the scripting process that could affect how direct said connections are. Personally, I doubt we'll see something terribly explicit, like a new army of battle droids.
Following Colin Trevorrow's departure from Star Wars: Episode IX in September, J.J. Abrams was brought aboard to conclude the trilogy he kicked off in 2015 with The Force Awakens. With Abrams as the new director and Chris Terrio tackling the latest draft, Episode IX has since been moved from May 2019 to December of the same year. So there's still quite a bit of time until principal photography kicks off. In the meantime, we're only two months away from Star Wars: The Last Jedi (helmed by Rian Johnson) from deliver the middle chapter of this trilogy.