In the original Star Wars trilogy, it was the Empire versus the Rebels. In the prequel trilogy, it was the Separatists versus the Republic. Now, 30 years after the end of Return of the Jedi, with the Emperor dead and the Rebellion victorious, two new factions have emerged to battle it out in Star Wars: The Force Awakens — meet the Resistance and the First Order.

The names come from Star Wars Celebration, discovered by attendees on prop versions of the spaceships and suits of armor used by the movie's characters. The Incom T-70 X-Wing — an upgrade on the T-65 X-Wing used in Episodes IV to VI — is the "signature combat craft of the Resistance forces in their fight against the First Order." But who are the First Order? And why have the Rebels become the Resistance? Surely victory at the battle of Endor, the deaths of the super-powerful Sith in control of Imperial government, and the sight of a thousand tiny Ewoks dancing their fluffy little hearts out helped the Rebels take rapid control of the galactic seat of power on Coruscant?

Maybe not. The expanded universe — a moment of silence, please — was always muddy on exactly how power transferred from the Empire to the hastily built New Republic after the destruction of the second Death Star. Rebel leader Mon Mothma assumed control of the new government, but it was a bit of a narrative fudge to mothball the vast military-industrial complex the Empire had built up, especially when worlds like Carida were dedicated almost totally to Stormtrooper training.

The First Order may represent an Empire that was never quite beaten. The trailer shows Stormtroopers marching under a suitably spiky logo that looks like a slight deviation on the Empire's previous crosshair-style crest. Thirty years later, the galaxy could still be split by the civil war, controlled in pockets by local governors. There's precedent for this kind of setup in the old expanded universe — the Hutts controlled Hutt space, the Corporate Sector avoided galactic governance, and the Hapes Consortium, near at the center of the galactic core, had its own royal family. There's precedent, too, for an Imperial Remnant: a group of worlds whose inhabitants preferred the tight control and snazzy uniforms that came with being a bad guy in Star Wars' galaxy. In the Legacy books and comics, the Remnant alternately fought against, and joined forces with, the New Republic, under the control of charismatic leaders like Admiral Thrawn and Gilad Pellaeon.

Or the First Order could be more explicitly evil. Kylo Ren, Episode VII's new big bad, bears a striking resemblance to Revan, the dark lord of the Sith who served as a pivotal character in the Knights of the Old Republic video games. If Ren is a Sith, has he pressed the Stormtroopers of the First Order into service for his nefarious schemes? The Sith have the Rule of Two, a dictum that states only two Sith can coexist — a master and his student. Perhaps Ren is the first of those two, and the order is his, given the name to show their allegiance. If Ren is in charge of the force, is his Sith-ness common knowledge, or is he copying Darth Sidious' approach, using a veneer of normality to make his dark-sided schemes politically acceptable? The fact that John Boyega, expected to be one of Episode VII's core heroes, looks likely to start the movie as a Stormtrooper suggests that the First Order could at least have an outwardly noble objective.

The Resistance has a clearer line to its original trilogy counterpart. Like the Rebels, the group uses X-Wings, and its pilots wear the same flight suits as their predecessors did to blow up the two Death Stars. But with both the Empire's boss and his right-hand man dead at Endor, why didn't the Rebels step in to fill the power vacuum? If the Resistance are the children of the Rebels, who exactly is the Resistance resisting? A revitalized Empire, able to regroup and push back after the devastating loss over the forest moon? A new Sith-led force? Or a new Republic, a flawed entity put together to fill the vacant seats in the Senate that quickly became corrupt or complacent?

We'll find out more as Star Wars Celebration unfolds this weekend, but we might have to wait until later this year to find out what these two new groups stand for. Director J.J. Abrams is keeping his sabacc cards close to his chest, and as yesterday's opening panel shows, new Star Wars faces like John Boyega aren't willing to give away much but the most basic details of their character origins.