The title Darth was a prefix attached to the name of a Sith Lord. Before the establishment of the Rule of Two, it was employed by ancient Sith individuals such as Darth Atrius, Darth Caldoth, and Darth Noctyss. Darth Bane's reforms ensured the continuation of the Darth title, leading to a thousand-year succession that featured figures like Darth Zannah, Darth Tenebrous, and Darth Plagueis. The culmination of generations of Sith was Darth Sidious, whose actions led to the rise of the Galactic Empire. Being a Sith Master, Sidious conferred the Darth title upon his three successive Sith apprentices: Darth Maul, Darth Tyranus, and Darth Vader.

The Sith Lords, a group of Force-sensitives who utilized the dark side of the Force to harness their power, were given the Sith title Darth, which functioned as both a name and a title. This title, which can be interpreted as "Dark Lord," was an integral part of a Sith Lord's identity, preceding a unique name that replaced their original one. The Darth title and the associated name together represented a Sith's identity. Sheev Palpatine, Dooku, and Anakin Skywalker's Sith names were Darth Sidious, Darth Tyranus, and Darth Vader, respectively. In at least a couple instances, the Sith Master bestowed the title and name upon their Sith apprentice. According to the Rule of Two, both the Master and apprentice held the Darth title at the same time.

The Sith were a sect of Force adepts who splintered away from the Jedi Order. Numerous Sith appended the title "Darth" to their names, including legendary figures such as Darth Caldoth, Darth Noctyss, Darth Sanguis, and Darth Wrend. When the Sith were numerous and powerful, Darth Atrius possessed the title. Darth Momin, Darth Ravi, Darth Shaa, and Darth Tanis were other individuals who bore the title.
Darth Krall, formerly known as Jedi Master Radaki, was a powerful Sith Lord who had once been a Jedi until he embraced the dark side of the Force. Radaki's belief that the Jedi should maintain their family connections and wealth clashed with the Jedi Code, eventually leading him to become one of the Lost Twenty. During the Sith Empire's occupation of Aaloth, Darth Quellus was rumored to have used the dark side to cause candles to burn black.
The Sith faced the threat of extinction due to internal conflicts and their battles with the Jedi. Darth Bane, the last survivor of the ancient Sith, established the Rule of Two—limiting their numbers to a master and an apprentice—by training Darth Zannah as his only follower.

Bane's lasting legacy endured for a millennium, resulting in a line of Sith Lords that reached its peak with Darth Sidious, who gained power as Sheev Palpatine during the late era of the Galactic Republic. Over time, the Sith tradition produced Darth Tenebrous, who instructed Darth Plagueis. Continuing the Rule of Two, Plagueis trained Darth Sidious; after mastering Plagueis' secrets, Sidious killed his master and trained his own apprentice, the Dathomirian warrior Darth Maul.
The Jedi High Council became aware of the Sith Order's resurgence during the Invasion of Naboo, triggered by Qui-Gon Jinn's initial encounter with Maul on Tatooine. The High Council was doubtful of Jinn's findings, as the Jedi had not faced a living Sith Lord in over a thousand years. Jinn's death in a lightsaber duel with Maul, during the Battle of Naboo, removed any doubt that the High Council had about the "mysterious warrior's" identity as a Sith. The High Council also suspected the existence of a second Sith Lord due to their awareness of the Rule of Two. However, they could not be certain whether the Sith who killed Jinn had been the master or the apprentice.
The name Darth Sidious was first revealed to the Jedi by a former member of their Order, Count Dooku, who informed Obi-Wan Kenobi about Sidious' influence over the Galactic Senate. However, neither Kenobi nor Grand Master Yoda believed Dooku, as they considered the Count's credibility compromised by his conversion to the dark side and betrayal of the Jedi Order. Nevertheless, Mace Windu advised the High Council to exercise greater caution in their future dealings with the Senate.

Sidious effectively maintained a dual existence throughout his rise to power, with the two aspects of his persona—Darth Sidious and Sheev Palpatine—working together to achieve the Grand Plan and the unlimited power he desired. By the end of the Clone Wars, he was declared the Galactic Emperor, which also involved the extermination of the Jedi throughout the galaxy under Order 66. As Emperor of the Galactic Empire, Sidious no longer saw any value in maintaining his Palpatine identity. Although the name "Palpatine" was included in his public title as Emperor, in his own mind he was only "Darth Sidious" for the remainder of his life.
Through her connection to Maul, Lady Qi'ra, the leader of Crimson Dawn, learned about the Sith, including the history of Darth Sidious. Opposed to the New Order, Qi'ra plotted to end the Sith's control over the galaxy with the assistance of the Knights of Ren and other allied groups. During the Galactic Civil War between the Empire and the Alliance to Restore the Republic, Qi'ra revealed Palpatine's Sith name to her allies while condemning his reign as Emperor.

Sidious took the Zabrak son of Mother Talzin, the child who would one day become Darth Maul, at a young age and trained him in the ways of the Sith. At some point, his master gave him the Sith name "Darth Maul," and he forgot his original birth name. As a Sith apprentice, Darth Maul was trained in secrecy until Sidious decided to reveal their Order's survival to the Jedi. Maul yearned to avenge his predecessors' defeat in the Jedi-Sith War of centuries past, but was defeated and nearly killed by Obi-Wan Kenobi. At the time, his name was unknown to the Jedi who referred to him simply as the "mysterious warrior." However, by the time of the Clone Wars, the Order had discovered his name. Kenobi initially mistook Savage Opress for Maul, who was his brother, because of their resemblance.
After recovering from his injuries, Maul sought to lead his own secret empire, the Shadow Collective. Despite no longer being Sidious' apprentice, he still regarded himself as a Sith Lord and assumed the role of master for his brother Opress. During the Battle of Mandalore, Sidious killed Opress and defeated Maul, stating that only two Sith Lords could exist at any given time.
Maul survived the Clone Wars and sought revenge against both the Jedi and Sith. Although he retained his connection to the dark side of the Force, Maul no longer identified as a Sith. Nevertheless, the Seventh Sister addressed him as "Darth Maul," to which the former Sith revealed that he had abandoned the title of Darth by the time of the Inquisitors' arrival on Malachor.

Following the Invasion of Naboo, former Jedi Master Count Dooku replaced Maul as Sidious' Sith apprentice and was subsequently renamed Darth Tyranus. Dooku had previously used the name Tyranus in his dealings with the Kaminoan government and the Pyke Syndicate. As his Sith name, he would use it in conversations with his Sith Master. However, he continued to use his original name in his public role as the Count of Serenno and Head of State of the Confederacy of Independent Systems. Throughout the Separatist Crisis and the Clone Wars, Tyranus and Sidious kept their Sith identities secret by using their public names, Dooku and Sheev Palpatine, respectively.
The Jedi Order gradually became aware of the plot to end their era of guardianship over the galaxy, starting when Kenobi learned that an individual named "Tyranus" had hired the bounty hunter Jango Fett to serve as the clone template for Sifo-Dyas' army of clone troopers. The Jedi discovered that the mysterious Tyranus was actually Dooku when the Pykes on Oba Diah addressed the Count by his Sith name in the presence of Kenobi and Skywalker. Their subsequent report to the Jedi High Council confirmed that the Sith were indeed responsible for the creation of the Grand Army of the Republic. By then, however, the Jedi had come to trust the clones who served under their command. The High Council was also aware of the impact the information would have on the Republic's morale; therefore, Grand Master Yoda instructed his colleagues not to reveal Dooku's role in the clone army's origins to anyone, including Chancellor Palpatine.

Sidious recognized the undeniable power of the Skywalker bloodline, even though he considered his own lineage to be the strongest in the Force. Consequently, he planned to eventually replace Tyranus with Anakin Skywalker. Skywalker, known as the Chosen One destined to bring balance to the Force, was inducted into the Jedi Order and trained by Obi-Wan Kenobi. Using his elevated position as "Chancellor Palpatine," the leader of the Senate, Sidious developed a friendship with the young Skywalker to ensure their future partnership as Master and apprentice.
Under Sidious' influence, Skywalker gradually succumbed to the dark side of the Force. During the Battle of Coruscant, he executed Tyranus on the orders of Chancellor Palpatine, who then revealed his secret identity as a Sith Lord to the Jedi. After thwarting the High Council's attempts to depose Sidious, Skywalker ultimately turned to the dark side. By pledging his allegiance to the Sith, Skywalker was deemed worthy of the name Darth Vader by Sidious, who took the former Jedi Knight as his new Sith apprentice. The newly named Vader led the 501st Legion's attack on the Jedi Temple, where he personally murdered numerous Jedi, including Jedi younglings who recognized him as Skywalker.
Kenobi and Yoda discovered Vader's actions in the Temple upon their return to Coruscant. Yoda's advice to separate Skywalker from the Vader persona replaced Kenobi's hesitation to confront his former Padawan with resolve. According to Yoda, Skywalker had essentially ceased to exist when he embraced the dark side. Vader was defeated and left to die on Mustafar by Kenobi, but Sidious intervened and rebuilt his apprentice into an armored cyborg.

After years of hunting his former master, Vader confronted Kenobi on a barren moon in 9 BBY. During the duel, Vader's mask was damaged by Kenobi's lightsaber. Upon seeing Anakin Skywalker's face, Kenobi apologized to his former friend, but Darth Vader declared that he was responsible for the destruction of his previous self. Convinced that Skywalker was truly lost to the dark side, Kenobi bid Vader farewell, addressing him as "Darth" instead of "Anakin."
During their final duel in 0 BBY, Kenobi found himself unable to say his old friend's real name and instead called him "Darth." In the aftermath of the Battle of Yavin, Sidious warned his apprentice to not underestimate how much he disappointed his master by losing to Kenobi on Mustafar. Sidious had given the title of "Darth Vader" to Anakin Skywalker because at the time he believed that the fallen Jedi was worthy of bearing a Sith name. Having grown more doubtful of his apprentice, Sidious required Vader to prove that he was still worthy of his title by overcoming the obstacles in his path to Sith ascendancy.

Jedi Masters Obi-Wan Kenobi and Yoda kept Darth Vader's former identity a secret from his son, Luke Skywalker. Although Skywalker eventually discovered that his father had served alongside Kenobi as a Jedi Knight in the Clone Wars, Kenobi sought to protect Skywalker from the complete truth of Anakin's fate. He informed Skywalker that his father was killed in the systematic purge of the Jedi Order by a fallen Jedi, Darth Vader. Skywalker strived to learn the ways of the Force as a Jedi, like his father, while believing Anakin to be dead until he confronted his father's "killer," Vader, in Cloud City on Bespin, where the Sith Lord revealed that he was the young Jedi's father.
As a Force spirit, Kenobi explained that his motive for hiding the truth was to protect Luke Skywalker. According to Kenobi, he had told the truth—from his point of view—about Vader's role in the "death" of Anakin Skywalker. Yoda had also referred to Vader and Anakin as different personas shortly after discovering his turn to the dark side. Vader and his Master, Sidious, alluded to the idea that Anakin was a separate person from Vader as well.
After Yoda and Kenobi confirmed Vader's identity, Luke Skywalker became convinced that he could turn his father back to the light side of the Force. Initially, Vader rejected his son's pleas to renounce the dark side and denied having any connection to the name Anakin Skywalker. However, during the Battle of Endor, Skywalker's compassion towards Vader caused him to protect his son from the Emperor in an act of self-sacrifice, resulting in his death as Anakin Skywalker rather than Darth Vader.

The prophesied downfall of the Sith occurred when Darth Sidious and Darth Vader eliminated each other, bringing an end to the thousand-year lineage that began with Darth Bane. However, unbeknownst to the galaxy, Sidious was resurrected after his initial death at Endor. Utilizing the knowledge he had gained from his late Master, Darth Plagueis, Sidious successfully transferred his consciousness to a clone of his original body through a dark-side technique known as Transference. In this new form, Sidious aimed to restore Sith rule throughout the galaxy.
Following Luke Skywalker's death, Sidious revealed his survival to the public through a galaxy-wide broadcast, leading to the search for Exegol by Supreme Leader Kylo Ren and the Jedi apprentice Rey—the respective descendants of Darth Vader and Darth Sidious. Although the First Order and the Resistance referred to the Emperor by his family name, Palpatine, Sidious made no attempt to conceal his Sith identity this time, declaring that the Sith Eternal's fleet, the Final Order, would usher in the rise of a new Sith Empire.
The Darth Malted Milkshake was a beverage sold in the galaxy. Darth Krist-Ov was a character in a tragic play performed during the Clone Wars. Darth Vader's name was remembered and hated for years after his death. During the First Order-Resistance War, Jedi Master Luke Skywalker mentioned his father and Sidious by their Sith names while recounting their history to the scavenger Rey.
The title "Darth" first appeared in George Lucas' 1977 film, Star Wars: Episode IV A New Hope, as part of the name Darth Vader. According to Star Wars: Behind the Magic, Lucas intended the name "Darth Vader" to mean "dark father." The Sith character Exim Panshard does not have "Darth" in his name, which author Adam Christopher interpreted as an indication that the Sith Order was not formally established with such titles at one point.