Despite beginning its life with the announcement that the Disney's Star Wars sequel trilogy by no means jettisoned or ignored the Star Wars EU entirely. While fans bemoaned the relegation of over 30 years of beloved Star Wars characters and stories to an extra-canonical status, filmmakers and screenwriters assured the renamed Star Wars Legends material would not necessarily lie fallow and unused. Though bearing little resemblance in plot, character, and even subject matter to the sequel series and spinoffs contained in the EU, Disney’s sequel trilogy still owes the Star Wars EU a significant creative debt.
While stating from the outset that the only canonical material would be the six original films and Grand iral Thrawn into mainline Stars Wars continuity, and the more recent Star Wars films and shows include more subtle references to the EU like allusions to the EU's Sith lore, and heretofore obscure Force powers.
Despite vast differences between the published sequel and books and comics and the sequel films released in the past five years, Disney continued this trend by lifting quite a bit of material from the EU for its sequel trilogy, giving the Star Wars Expanded Universe continued relevance despite its non-canonical status.
Emperor Palpatine Returning As A Clone
The most blatant lifting of EU material came in the concluding film of the sequel trilogy, Return of the Jedi, seeming a decayed husk of his former self. It's not explicitly stated in the film that the decrepit-looking Palpatine is a clone and not the actual Palpatine Redivivus, but it does drop hints, mainly through the character design, that all is not as it seems. The film's novelization more broadly hints at the possibility, when it has Kylo Ren theorize about cloning as the likely reason for Palpatine’s reappearance.
The idea of a Palpatine clone is pulled from from 1991's Dark Empire comic series, wherein Luke Skywalker, in response to the threat of Imperial remnants rallying together, discovers a youthful clone of Palpatine on the planet Byss, learning Palpatine has a virtually limitless supply of bodies into which he can transfer his consciousness, effectively giving him immortality. The story between Palpatine and Luke proceeds similarly to the Kylo Ren/Palpatine story in the final film, with Luke succumbing to the temptations of the revivified Palpatine and becoming his apprentice, while Leia receives visions of Luke's corruption and traverses the galaxy to save him.
The Rise of Skywalker is perhaps the only sequel film to take a plot element wholesale from the EU material. Why Disney chose to go in this direction is, ittedly, a bit of a mystery. Disney's lack of a plan when creating the sequel trilogy is now common knowledge, so perhaps the reintroduction of Palpatine was part of J.J. Abrams' and Disney's attempt to backpedal from Rian Johnson's more subversive and controversial story decisions, and the method of resurrecting Palpatine from the Dark Empire comics seemed like a logical method of returning him to cinematic life.
Leia Training As A Jedi
In the EU, after wrestling with her legacy as the daughter of Anakin Skywalker/Darth Vader, Leia eventually embraced the Force Sensitivity she briefly exhibited in the original trilogy and trained with her brother and a Jedi named Saba Sebatyne. In the New Jedi Order series (1999-2003), Leia becomes a full Jedi Knight as her children (three in this continuity) reach adulthood, fighting for the New Republic alongside the reformed Jedi Knights. The Rise of Skywalker, Leia abandoned her Jedi training after receiving a vision that told her completing her training would lead to her son’s death. Both the EU and the sequel trilogy incorporate the logical second-step of Leia exploring and dealing with her Force-sensitive legacy, even training as a Jedi eventually, but only the EU had her complete the training and become a Jedi Knight alongside her legendary brother.
While the sequel trilogy does include further instances of Leia displaying Jedi-like control of the Force - from her unexplained, self-propelled rescue from the vacuum of space at the beginning of The Last Jedi to using the Force to call out to her son in her dying moments in The Rise of Skywalker - she continues the role she played in the original trilogy, as a diplomat and leader of a military resistance movement. Despite the EU tending toward the Jedi for Leia's character, the idea of Leia becoming a Jedi was never a totally uncontroversial idea, with fans weighing in with valid arguments on both sides of the debate.
Disney then, in telling their own story and trying to appease fans at the same time, probably decided to meet in the middle on this issue. Leia does develop her Force-sensitivity off-screen, showing more command of the Force than she displayed in the original trilogy, but, never fully committed herself to the Jedi Order, choosing to remain outside it for reasons both personal (concern for her son) and professional (her tireless devotion to democracy and the Rebellion).
The Son of Han and Leia Turning to the Dark Side
The notion of the Han and Leia marrying and having children of their own is nothing new, but the Star Wars sequel trilogy bears more than a ing resemblance to the EU in including a son of Han and Leia who turns to the dark side. In the EU, Han and Leia eventually have three children, twins Jacen and Jaina, and a much younger son, Anakin. Jacen learned the ways of the Force from his uncle, Luke Skywalker, but was eventually seduced to the dark side by his experience in war, becoming Darth Caedus, apprentice of Lumiya, the "Dark Lady of the Sith."
Kylo Ren’s arc does mirror Jacen’s descent into the dark side: both are nephews of Luke Skywalker, both trained in Luke's newly-formed Jedi academy, both were eventually drawn away from the path of the straight and narrow by the lure of their dark ancestry and their frustration with the limitations of the Jedi code, taking on new Sith names, and both cemented their descent into the dark side by murdering their loved ones (for Kylo, killing Han Solo, for Jacen, killing his aunt Mara Jade).
However, the details are enough to make them completely different characters. Jacen spends a long time training as a Jedi and fighting evil alongside his family before turning to the dark side, whereas Kylo Ren is seduced away by Snoke while still training under Luke. Jacen's torture and experiences in war are a significant factor in his turn towards the dark side, and, despite all his ambivalence to the traditional ways of the Jedi, Jacen never wholesale murders Luke's Jedi academy as Kylo Ren and the Knights of Ren did in the sequel trilogy. In general, Jacen's transformation into Darth Caedus is a much slower process than Ben Solo's transformation into Kylo Ren. While borrowing certain basic elements from Jacen Solo's story in the sequel trilogy, Disney decided to keep most of Kylo Ren's descent into the dark side in the background, keeping the question of how he became evil a question of fan speculation, for better or for worse.
A Skywalker Child Named Ben
Further, Kylo Ren's real name is borrowed from Ben Skywalker, Luke's son with former "Emperor's Hand" Mara Jade, a character created by Timothy Zahn in his 1991 novel, Heir to the Empire. A complex and fascinating character, she eventually betrays her former employers and s the Rebellion and New Republic, and later weds Luke and has a son with him, Ben Skywalker. Since the prequel trilogy established that Jedi cannot marry and Anakin was guilty of an egregious breach of the Jedi code in marrying Pe Amidala, Luke obviously could not name a son after his beloved mentor, so the next logical step for the filmmakers was to the name on to Han and Leia's only child.
In the EU, Han and Leia did name a child after a famous Jedi in their lineage, Luke and Leia's grandfather Anakin, but in a universe wherein Jedi can sire children without significant controversy, Luke naming his son after Ben Kenobi arguably makes more sense than Han and Leia choosing that name for their son. Luke was much closer, in life and in death, to Ben than Leia ever was; while Leia did famously plead for Obi-Wan's aid at the beginning of A New Hope, never once in the original trilogy did she even speak to Ben Kenobi, let alone enjoy the kind of friendship that Luke enjoyed with Obi-Wan. She and Han might have given their son his name out of respect for her brother and his mentor, but it seems more likely that, as in the EU, they would choose a name more relevant to their lineage.
Luke's Jedi Academy
As in the films, the EU novels, specifically the 1994 Jedi Academy trilogy by Kevin J. Anderson, featured Luke founding a Jedi Academy and training a new generation the Order's knowledge had been lost for decades, but in the EU it lasted longer and had a higher success rate than Luke’s doomed school in the sequel trilogy. As in the films, one of Luke’s students, his nephew Jacen Solo, went rogue and became evil, but unlike the film, students went rogue on a semi-regular basis, without Luke losing heart and dumping the whole enterprise based on the failure of one student. Some of his rogue students even became fan favorites of sorts, with characters like Kyp Durron, another of Luke's students who defected to the Dark Side, arguably providing inspiration or even a template for Kylo Ren's character arc.
In the EU, Luke became the forefront of a Jedi Renaissance of sorts, unlike in the films, or at least in The Last Jedi, where he seems disillusioned with the whole enterprise and sees little point in restoring or resurrecting the Jedi Order. The change probably comes from the difference in how the story of the Jedi Order is told in the EU versus the films; in the EU, Jacen's turn to the dark side comes years after the Academy began, giving Luke enough confidence in his Academy to not let the failure of one, or even a handful of students discredit the whole endeavor. In the films, Ben Solo is his only nephew and one of his first students, so the failure hits him much harder, especially with no previous successes to soften the blow.
Disney will probably never directly adapt any story or novel from the EU, but none of that will stop current or future creators from borrowing plot elements, story ideas, motifs, or even whole characters, for its Star Wars movies, shows, and more going forward. The EU is far too expansive, far too beloved by fans, too rich in ideas and storytelling potential to be dismissed entirely. If the sequel trilogy is any indication, fans will be seeing more familiar characters, stories, and ideas in new guises in new Star Wars content in the near future.
