When Disney acquired Lucasfilm in 2012, one of the first orders of business was to organize a comprehensive Star Wars canon. Controversially wiping out the old Expanded Universe and piecing together a Lucasfilm story group, the goal was to make each and every piece of Star Wars media connected and all part of the same storyline. This meant that anything that happened in a movie, television show, book, or comic was part of the official continuity. Even the video game Star Wars Battlefront featured the Battle of Jakku - the aftermath of which can be seen in Star Wars: The Force Awakens.
While the non-film canon materials are a great way for fans to experience more of the galaxy far, far away (and flesh out characters), they've never really been required viewing or reading to enjoy the full length features. Someone who read the book Aftermath before seeing Episode VII may have a better idea about the state of the universe post-Return of the Jedi, but fans who didn't pick up the novel weren't lost. That could be read as a conscious decision on Lucasfilm's part to keep things "separate but connected" to maintain a level of accessibility for all they release. It will be interesting to see if that changes down the line, especially with Star Wars: Episode VIII director Rian Johnson helping develop the upcoming novel Bloodline.
A post on the Star Wars website covering why Bloodline (by Lost Stars author Claudia Gray) is essential reading reveals that "some of the story ideas and elements in this novel came straight from Rian Johnson." Exactly what he contributed remains a mystery, but his involvement is noteworthy. This marks the first time in the new Star Wars canon that a film director has publicly been confirmed to provide ideas for a book, suggesting that there will be strong ties between Bloodline and the upcoming Episode VIII.
For those not in the know, Bloodline takes place six years before The Force Awakens and revolves around Leia Organa. It looks to answer some of the questions fans had after seeing Star Wars 7, including the origins of the Resistance and the formation of the First Order. In the novel, the New Republic is splitting into two factions: Populists (like Leia), who believe individual planets should retain their authority, and Centralists, who feel that a strong government and military is the way to go. The Force Awakens novelization stated that Leia views herself as a "political pariah" and doesn't have the full support of the Republic while waging a war. How things got to that point is the primary focus of the new book.
With Johnson directly adding aspects to Bloodline, it would seem that his film will dive into the political side of the spectrum, portraying a fractured Republic reeling from the destruction of the Hosnian system. This would certainly be new material for the movies to explore, lending credence to Oscar Isaac's statement that the project will tackle "different things" that he never expected. Rumors about Laura Dern's new mystery character indicate that she could be an idealogical opponent of Leia's, potentially setting the stage for a "civil war" of sorts in another massive Disney blockbuster. Time will tell, of course, but that would be a fascinating concept and fresh ground for the franchise to cover.
In the meantime, fans have another reason to pick up Bloodline when it hits shelves in May. Gray's previous Star Wars book, Lost Stars, was very well-received, and readers can't wait to see what she comes up with this time around. Add in the fact that Johnson could be planting some of the seeds for Episode VIII roughly a year and a half before the film premieres, people will be going over each page carefully for clues and revelations.
Star Wars: Bloodline will be released May 3, 2016. Rogue One: A Star Wars Story opens in theaters on December 16, 2016, followed by Star Wars: Episode VIII on December 15, 2017, the Han Solo Star Wars Anthology film on May 25, 2018, Star Wars: Episode IX in 2019, followed by the third Star Wars Anthology film in 2020.