Unknown Regions

"Everything is rough in the Unknown Regions."

- General Leia Organa

The Unknown Regions, also referred to as Unknown Space and the Unknown Territories, was a region of the galaxy located in the galactic west beyond the Outer Rim. Largely unexplored throughout galactic history, it remained a mystery to space travelers and served as a source of tales and wonders.

Description
At the time of the Galactic Civil War, the Unknown Regions was regarded as an unexplored region that was separated from the galaxy by a labyrinth of solar storms, rogue magnetospheres, black holes, gravity wells, and things far stranger. Strange creatures were known to inhabit the void. This maze was considered impassable and many exploration ships and probe droids were lost trying to breach it. By the time of the Battle of Jakku, Imperial computers at the Jakku Observatory had found a safe route through this maze which involved taking multiple short hyperspace jumps through the maze. This journey took several months.

Planets within the Unknown Regions included Ilum system, the most notable of the system would be the planet Ilum. Other planets included The Deep, Rakata Prime, Tehar. The regions notably housed the First Order's stronghold, Starkiller Base as well as the First Jedi Temple which was found on the watery world of Ahch-To. Political governments such as the Chiss Ascendancy were native to the region, this included the home planet of the Chiss, Csilla.

According to the Z7 series construction droid Zeta, there were few service centers, mechanics and factories for replacement parts in the Unknown Regions and no self respecting droid ever ventured there.

Ancient history
Dating as far back as the Old Republic, the Jedi Order was known to utilize the planet Ilum as a source of kyber crystals, which were important in the construction of a Jedi's lightsaber. At a young age, Jedi younglings were sent to Ilum to retrieve these crystals, traveling into the Unknown Regions aboard a ship known as the Crucible.

Galactic Empire
"These aren't civilian targets. They're Imperial installations staffed by people who have bought into the Emperor's sick vision of the future&mdash;for you, your queen, me, and everyone between here and the Unknown Regions."

- Berch Teller

During the early years of the Galactic Empire, some dissidents, such as Berch Teller, believed that the Empire would extend all the way to the Unknown Regions. The existence of "evil threats" in the Unknown Regions led the Chiss Ascendancy to send the future Grand Admiral Thrawn to forge an alliance with the Galactic Empire. Thrawn made first contact with the Empire by posing as an exile. He eventually gained the trust of Emperor Palpatine and Colonel Wullf Yularen. Following the Batonn insurgency, Thrawn sent his friend Commander Eli Vanto to serve as an Imperial liaison with the Chiss Ascendancy.

During the Age of the Empire, the Emperor sent several explorers to explore the Unknown Regions. Many of these explorers were killed while trying to breach the maze that lay to the west of Jakku. Others went mad from isolation. Palpatine's efforts to map the Unknown Regions were aided by the Chiss Admiral Thrawn, a native of the Unknown Regions. Following the Battle of Endor, Palpatine's former adviser Yupe Tashu advocated that the Empire venture into the Unknown Regions to seek out the source of the dark side of the Force.

Palpatine also operated a secret observatory on the planet Jakku which contained powerful ancient computers that generated a computerized three-dimensional map of the Unknown Regions. The Observatory's computers dispatched numerous probe droids to test the routes that the computers had generated. Shortly before the Emperor's death at the Battle of Endor, the computers finished their calculations and found a safe path into the Unknown Regions. As a result, the Emperor's flagship Eclipse was dispatched into the new frontier. Following the Battle of Jakku which saw the death of Counselor to the Empire Gallius Rax, Grand Admiral Rae Sloane, Brendol Hux, and other Imperials used these coordinates to travel through the Unknown Regions and rendezvous with the Eclipse.

First Order
Following the signing of the Galactic Concordance which ended the Galactic Civil War and dissolved the Old Empire, the Imperial remnants retreated from the known galaxy and relocated to the Unknown Regions. There, they established a militaristic remnant faction that became known as the First Order.

Shipyards, weapons factories, base installations were established within the Unknown Regions.

In 34 ABY, Starkiller Base served as a major base for the First Order. The First Order later used its phantom energy to destroy the Hosnian system, which hosted Hosnian Prime, the capital of the New Republic. The First Order then attempted to use Starkiller Base to destroy the Resistance base on D'Qar in the Ileenium system in the Outer Rim Territories. However, the Resistance destroyed Starkiller Base, dealing a serious blow to the First Order.

Following the destruction of Starkiller Base, Rey traveled to the Unknown Regions world of Ahch-To to seek out Jedi Master Luke Skywalker. A greatly reluctant Skywalker agreed to train her in the Jedi ways. After Rey returned to the wider galaxy in an attempt to redeem Kylo Ren, Skywalker decided to aid the Resistance by using a Force projection to distract Ren during the Battle of Crait so that the Resistance could escape offworld aboard the Millennium Falcon with Rey and Chewbacca. The stress created by the Force projection proved too great and Skywalker became one with the Force.

The Unknown Regions were used by the First Order to hide the Supremacy before the Battle of Crait.

Behind the scenes
The Unknown Regions were originally introduced in the Heir to the Empire Sourcebook, which was an accompaniment to the Legends novel Heir to the Empire. It was brought into canon when the planet Ilum was introduced in the Star Wars: The Clone Wars episode "The Gathering".

Pablo Hidalgo explained in Rebels Recon that the borders of the Unknown Regions were known (and therefore should be visible on the map of the galaxy) but what were within the regions were unknown. This would be in contrast with Wild Space, which was outside the known map of the Galaxy (in other words, 'off the edge of the map').

Non-canon appearances

 * LEGO Star Wars: The Force Awakens