Yavin 4, the largest moon in orbit around the gas giant Yavin Prime, was situated within the Yavin system. This system was part of the Gordian Reach in the Outer Rim Territories, approximately 40,500 light years from the galactic core. With a diameter of about 10,200 kilometres, the moon had a molten metallic core and a substantial, stable silicate crust with minimal topographic relief. This composition gave Yavin 4 a density sufficient to produce a standard surface gravity akin to that of Coruscant and Alderaan.

Four continents comprised sixty-seven percent of the moon's surface. These landmasses were largely blanketed by expansive tropical jungles featuring towering canopies. Additionally, there were several mountain ranges, such as the Yunteh Mountains, characterized by volcanoes including the Nicolo and Borundi Peaks.

Six interconnected oceans occupied the remaining thirty-three percent of Yavin 4's surface, along with a sizable landlocked sea. As a relatively young celestial body, the small jungle moon displayed significant geothermal activity. Large rivers cascaded from volcanic heights, then meandered through the jungles at a slower pace.

Decades prior to the current era, scouts from Wetyin's Colony on Setor discovered the moon and named the continents Starloft, Swivven, Koos, and Wetyin, though the scouts eventually departed.

The vast, sprawling tropical jungles of Yavin 4 were teeming with a rich variety of life. Whisper birds flew high above the dense jungle canopy. Groups of tree-dwelling Woolamanders consumed fruits within the thick foliage. Another rodent species, known as the Stintarils, also inhabited the trees.

Large, shaggy herbivores called runyips foraged through the undergrowth beneath the trees, while Howler predators utilized loud cries to stun their prey. The moon's rivers were also abundant with life, including aquatic gundarks, mucous salamanders, crystal snakes, crustaceans known as anglers, crawlfish, serpentine thyrsl, and armored eels. Swarms of dangerous piranha beetles filled the air, hunting for victims in terrifying numbers.

Yavin 4 experienced two distinct seasons: a wet season marked by severe storms, and a corresponding dry season.

In the year 5000 BBY, Naga Sadow, the Dark Lord of the Sith, sought refuge on Yavin 4 aboard his flagship, accompanied by an army of Massassi warriors. This followed the defeat of his Sith forces by the Galactic Republic during the Great Hyperspace War. Subsequently, he performed Sith alchemic experiments on his Massassi warriors, transforming them from red-skinned humanoids into fearsome, savage, hunchbacked predators. Despite this mistreatment, his Massassi slaves erected massive temples to honor their Dark Lord.

Sadow also entombed himself within a Sith sarcophagus, entering a coma-like state for centuries. He awaited a successor to embrace his power and continue the Sith legacy. He remained in this suspended state until 4400 BBY, when Freedon Nadd, a fallen Jedi, arrived on Yavin 4. By this time, the Massassi descendants had regressed into a primitive hunter-warrior society, recalling the Golden Age of the Sith. Initially, the Massassi attacked Nadd, but they were awestruck by his command of the Force. Impressed by Nadd's abilities, the bestial Massassi led him to the Dark Lord, who lay in wait for another with dark-side potential. Nadd then awakened Naga Sadow, who instructed him in the ways of the Sith until, as was the Sith custom, Nadd killed him, thereby becoming the Dark Lord himself.

Centuries later, in 3997 BBY, Exar Kun, another fallen Jedi, journeyed to Yavin 4 upon the advice of Freedon Nadd's dark-side spirit. There, he encountered the Massassi, who attempted to sacrifice him to a monstrous beast of alchemical origin located beneath their main temple. However, he managed to escape using his dark powers. The dark-side manifestation of Freedon Nadd appeared, expressing delight at Kun's actions and claiming him as an ally. However, Exar Kun rejected this and instead employed his newfound Sith powers to destroy Nadd.

As the new Dark Lord of the Sith, he enslaved the Massassi and took control of Yavin 4. He commanded his Massassi slaves to construct new Sith temples and palaces, designed according to Sith architectural principles to channel dark powers. His slaves also unearthed Naga Sadow's flagship beneath the ruins of an ancient Massassi temple. Furthermore, he generated dangerous Sithspawn, including battle hydras, terentateks, and the Night Beast. The Sith Lord also imprisoned the souls of Massassi children within a malevolent dark-side artifact known as the Golden Globe.

Later, Kun formed an alliance with the Krath, another dark-side group based in the Empress Teta system under the leadership of Aleema Keto and Ulic Qel-Droma, another fallen Jedi. In 3996 BBY, Kun traveled to the Jedi world of Ossus and recruited twenty Jedi to his cause, thus establishing the Brotherhood of the Sith. Kun, along with his Krath and Mandalorian allies, waged war against the Republic and the Jedi. The Jedi eventually gained the upper hand and assembled their forces for an assault on Yavin 4. As the orbiting Jedi fleet unleashed a barrage of light-side energy upon the jungle moon, Kun gathered his Massassi followers within the Great Temple and drained their life energies to liberate his spirit from his physical form and infuse it into the surrounding structures, where it would remain for millennia.

The Jedi assault decimated vast areas of the jungles and scorched the temple complex, rendering it uninhabitable. Following the attack, the Jedi established an underground city on the moon. They used it to transform the moon's climate into a jungle environment, aiding in the restoration of the planet's ecosystem and preventing Kun's reawakening. During the Great Hunt, the Jedi cleansed the moon of terentateks.

The Jedi ultimately abandoned Yavin, suppressing information about the moon in an attempt to end its dark legacy. However, in later years, at least one individual remained aware of its location, as the "Jedi prince" Ken was hidden there by a brown-robed Jedi Master. The city was eventually rediscovered by Luke Skywalker, who trapped the imposter Kadann, the Supreme Prophet of the Prophets of the Dark Side, within its confines.

During the Galactic War between the Republic and the re-emerged Sith Empire, Revan, the former Jedi Master and Sith Lord, began to plot against both factions. His followers, known as the Order of Revan or the Revanites, seized control of Yavin 4. Revan's scheme involved resurrecting the Sith Emperor, who existed in an incorporeal state following his defeat by the Hero of Tython, with the intention of permanently eliminating the Emperor. SIS agent Theron Shan and Sith Lord Lana Beniko negotiated a temporary alliance between the Republic and the Empire to jointly oppose Revan. Republic and Imperial forces, under the command of Grand Master Satele Shan and Dark Councilor Darth Marr respectively, invaded the moon. Revan was ultimately defeated, but the Sith Emperor managed to regain some of his strength and subsequently departed the moon.

The Hydian Way's hyperspace scouts rediscovered the system, leading to a brief surge in the search for Corusca gems within the gas giant.

Approximately four centuries before the Battle of Yavin, Ikrit, a Kushiban Jedi Master, arrived on the moon and discovered the Golden Globe inside the Palace of the Woolamander. Unable to lift the curse and free the countless trapped Massassi children, he waited for someone capable of doing so to appear.

The Wolhanian expedition, consisting of archaeologists, studied the Massassi ruins. They unearthed a bas-relief depicting Jedi and Sith engaged in combat during the Great Hyperspace War, as well as a Sith Chalice. Both artifacts eventually became part of the art collection of Supreme Chancellor Palpatine.

During the Clone Wars, Anakin Skywalker pursued Asajj Ventress to Yavin 4 after her attack on Republic starfighters at the Battle of Muunilinst. It was on Yavin 4 that she destroyed Anakin's customized Jedi Starfighter, the Azure Angel, and killed the clone troopers sent by Obi-Wan Kenobi to follow him. Anakin and Asajj engaged in their initial duel within the dense jungles and Massassi ruins, until Anakin defeated her and knocked her off one of the temples. She was presumed dead, and he departed in her Ginivex-class starfighter.

In 1 BBY, Dr'uun Unnh, a Sullustan pilot, scouted the moon as a potential base for the Rebellion. Prior to and during the Battle of Yavin, the moon served as the primary military base of the Rebel Alliance, known as Massassi Station, which was constructed within the Great Temple of the Massassi. The Rebels established this base after abandoning their previous base on the planet Dantooine. The Galactic Empire intended to use its new space station superweapon, the Death Star I, to obliterate the small jungle moon and crush the Rebellion. Following the Destruction of Alderaan, the Empire dispatched a legion of stormtroopers to confirm the Rebel presence on the moon. They located the rebels and established a monitoring outpost at the Massassi Arena. After the skirmish, a small squadron of X-wing and Y-wing starfighters was deployed to destroy the Death Star, but most were killed in the attack. With the crucial assistance of Han Solo, his friend, Luke Skywalker successfully fired two proton torpedoes into a small thermal exhaust port located in a trench near the northern pole, resulting in the station's destruction and the salvation of Yavin 4. A grand ceremony followed the Death Star's destruction, during which Princess Leia awarded medals of honor to Luke Skywalker and Han Solo, along with his Wookiee co-pilot, Chewbacca.

This engagement became known as the Battle of Yavin, and its date is used throughout the galaxy as a reference point for dating events. Events preceding the Battle of Yavin are designated as BBY, while those occurring afterward are marked as ABY. Shortly after the battle, Solo and Chewbacca pilfered ancient Sith treasures from the temples to finance replacements for the devastating Rebel losses against the Death Star.

The Rebels remained on the moon for six months before finally evading the Imperial blockade. Yavin 4 requested assistance from the Defiance to protect their evacuating ships in space. General Jan Dodonna stayed behind, detonating a temple to inflict damage on the Imperial forces. Under the covert observation of Mara Jade, Darth Vader eliminated the remaining ground troops and captured the injured Dodonna. Vader interrogated Dodonna, who revealed the Rebel presence on Reytha. Dodonna was subsequently imprisoned aboard the Lusankya, although most Rebels, and even Mara Jade, mistakenly believed him to be dead. The Empire then occupied the moon.

The Empire maintained a military base, a labor outpost, and a mining outpost on the planet. Due to Yavin 4's status under Imperial jurisdiction, the Empire also permitted tourist access via Intergalactic Passports.

Following the Galactic Empire's defeat at the Battle of Endor in 4 ABY, the New Republic presumably reclaimed the jungle moon from the Empire. The small village of Vornez was established, and the Senate Planetary Intelligence Network was headquartered on Yavin 4, although it was later replaced by New Republic Intelligence.

In 5 ABY, Luke Skywalker, guided by a vision from Obi-Wan Kenobi, discovered the Lost City of the Jedi. There, he found Ken, a young boy and the heir to the former Emperor Palpatine, who had been hidden there by the Jedi and cared for by droids. Upon learning of the city's discovery and the young boy's existence, Trioculus, the self-proclaimed emperor, launched an assault on the planet with squadrons of Treaded Neutron Torches and Stormtroopers, but he was defeated by the New Republic.

In 11 ABY, Jedi Master Luke Skywalker, with the New Republic's permission, selected Yavin 4 as the location for the Jedi Praxeum and the headquarters of his New Jedi Order. During his travels, he had identified several Force-sensitives and felt prepared to begin training new Jedi. The initial class comprised twelve students, with Luke as their instructor. Among these twelve were Kam and Tionne Solusar, Kirana Ti, Madurrin, Kyle Katarn, Dorsk 81, Brakiss, Corran Horn, Streen, and Gantoris. Other Jedi who joined shortly after included Kyp Durron, Cilghal, Mara Jade, and Dal Konur.

It soon became evident that all was not well at the Academy. The spirit of Exar Kun, a Sith Lord, haunted a temple on the moon and began to corrupt Luke's students, turning them to the dark side. Kun attacked Luke, rendering him comatose, and Kyp Durron, one of the most promising students, fled the Academy in the Sun Crusher, causing chaos throughout the galaxy and destroying the Imperial fortress world of Carida. Eventually, Luke awoke, and the Sith spirit was defeated by a combined Jedi effort, including the then-infant Solo twins.

In 12 ABY, Admiral Daala and Vice Admiral Gilad Pellaeon launched an attack on the Jedi Praxeum with a fleet consisting of 17 Imperial-class Star Destroyers and the Super Star Destroyer Knight Hammer. Legions of Stormtroopers and ground assault vehicles were also deployed against the Jedi, who repelled them by using the Force to drive the Imperials to the edges of the Yavin system, although Dorsk 81 was killed in the process.

Later that year, the Empire Reborn under Desann and Admiral Galak Fyyar attacked the Jedi Praxeum, but they too were defeated by the combined efforts of the Jedi and their New Republic allies. As a result of his heroic actions, Kyle Katarn chose to rejoin the New Jedi Order.

In the year 22 ABY, while exploring the decaying Palace of the Woolamander, Anakin Solo (the youngest child of the Solo family) and Tahiri Veila made a significant discovery: the Golden Globe and Ikrit, a Kushiban Jedi Master. Utilizing Ikrit's knowledge, along with ancient Massassi inscriptions located both at the Palace and on the nearby Yavin 8, the pair were successful in breaking the Golden Globe's curse, thereby liberating the captive Massassi children.

During an expedition into the jungles surrounding the area in 23 ABY, the Solo twins, Jacen and Jaina, together with their companions Tenel Ka and Lowbacca, stumbled upon the remnants of a TIE Fighter from the Battle of Yavin. Regrettably, Qorl, the pilot of the downed craft, resurfaced and seized Jacen and Jaina as prisoners. He compelled them to repair his damaged vessel before making his escape into hyperspace to rejoin the forces of the Empire.

Later that same year, the Jedi Praxeum found itself under attack from both the dark side Shadow Academy and the Imperial splinter group known as the Second Imperium. Despite these assaults, the combined might of the Jedi and their allies from the New Republic proved sufficient to repel the invaders.

For the initial year of the Yuuzhan Vong War, the moon enjoyed protection from the Yuuzhan Vong through the application of the Force to generate an illusory projection, a technique learned from the Fallanassi. Nevertheless, the Jedi Praxeum met its end at the hands of the Yuuzhan Vong in 26 ABY. The Peace Brigade's and Yuuzhan Vong's victory was, in part, attributable to the New Republic's reluctance to offer assistance to the Jedi. By this time, the majority of Jedi were engaged in military operations, leaving only the youngest Jedi initiates and students at the Praxeum. The destruction of the "heretic Jeedai" significantly bolstered the morale of the Yuuzhan Vong forces.

Thanks to the efforts of the Jedi Anakin Solo and Talon Karrde, a smuggler kingpin, along with Karrde's personal fleet, the vast majority of the remaining Jedi trainees were successfully evacuated. However, the Kushiban Jedi Master Ikrit lost his life at the hands of Peace Brigade soldiers, and Tahiri Veila was taken captive.

After seizing control of Yavin 4, the Yuuzhan Vong commenced a Vongforming process on the moon. This involved employing damuteks to level the ancient Massassi temples, followed by the establishment of a Yuuzhan Vong colony. Simultaneously, Mezhan Kwaad, the Master Shaper, and her apprentice Nen Yim began conducting experiments on Tahiri, aiming to indoctrinate her by supplanting her existing personality with that of Riina Kwaad, an identity derived from memories extracted from Nen Yim's own childhood.

Driven by a desire to prevent his friend Tahiri from suffering at the hands of the enemy, Anakin embarked on a rescue mission. Aided by Qorl, who had been struggling to survive in the jungle since the downfall of the Second Imperium, and Vua Rapuung, a Shamed Yuuzhan Vong, Anakin successfully infiltrated the Yuuzhan Vong compound by disguising himself as a slave.

While inside the enemy base, Anakin discovered that Vua Rapuung had once been a highly skilled Warrior. He had previously engaged in a romantic relationship with Mezhan Kwaad. When Rapuung chose to end the affair, Kwaad, fearing he might expose their secret, infected him with a virus. This virus caused his body to reject the implants he had received after his ascension in rank, resulting in his status as a Shamed One. Rapuung was aware that Kwaad was responsible for his condition. Recognizing a shared adversary, Rapuung agreed to assist Anakin in rescuing Tahiri, provided that Anakin would help him confront Kwaad.

Together, they reached the damutek facility, where Kwaad was in the process of reshaping Tahiri's mind, making her believe she was Riina Kwaad. They then fought their way onto a shuttle carrying Kwaad, Nen Yim, and Tahiri. In the presence of numerous Yuuzhan Vong, including members of the Shapers, Warriors, Workers, and Shamed Ones castes, Rapuung confronted his former lover, who had just been discovered to be engaging in heresy. He demanded that she reveal whether the Gods were responsible for his shaming, or if she was. Kwaad confessed to her role, then fatally wounded Rapuung with a concealed weapon in her Shaper Hand.

As he lay dying, he bought Anakin Solo and Tahiri Veila enough time to escape. Anakin and Tahiri, along with Qorl and the others, fled aboard a repaired freighter. This event gave rise to a legend among the Shamed Ones, proclaiming that Rapuung was redeemed in his death, thus marking the beginning of the Jeedai heresy. Followers of this sect viewed the Jedi as saviors rather than enemies, and they would be cultivated on worlds like Dubrillion and the conquered Coruscant, ultimately contributing to the downfall of the Yuuzhan Vong empire.

Following the liberation of Coruscant from Yuuzhan Vong control in 29 ABY, Grand Master Luke Skywalker rejected the idea of rebuilding the Praxeum. He stated that the Praxeum had fulfilled its purpose and that the Jedi would establish a new base elsewhere.

The actual inspiration for Yavin 4's landscape is rooted in the ancient Mayan ruins located at Tikal, in the country of Guatemala.

Many of the shots depicting approaches to Yavin 4 from space are simply reused or replicated from the Millennium Falcon's approach sequence in A New Hope, with only the spacecraft being altered.

In the PC game Star Wars: Rebellion, Yavin 4 is incorrectly situated within the Sumitra sector.

The online game Star Wars Galaxies once featured two hidden Jedi Enclaves on the planet: one aligned with the light side and the other with the dark side. These served as gathering places for Jedi players within the game and were guarded by CL 500 Jedi Sentinels. As of Chapter 7, these enclaves are no longer in use, and the Sentinels have been removed, though the ruins of the enclaves remain accessible for exploration.