Very few people knew that Darth Vader and Anakin Skywalker were the same person up to his death in 5 ABY. Imperials who knew in the current canon: Sidious (emperor), Grand Moff Tarkin, all or most of the Inquisitors, Grand Admiral Thrawn, various clones in the early empire.
Darth Vader's true identity as Anakin Skywalker was a highly guarded secret, known only to a select few individuals including Palpatine, Obi-Wan Kenobi, Luke, Han, Leia, R2-D2, C-3PO, Master Yoda, Bail Organa, Ahsoka Tano, Darth Maul, Grand Moff Tarkin, Grand Admiral Thrawn, Jocasta Nu, Ferren Barr, Verla, Reva, ...
Though it sounds like he thinks Anakin is dead, he could also be viewing it as Obi-Wan does, where he believes Anakin died when Darth Vader was created. There's a hint that Owen knows Anakin was Darth Vader by the time of A New Hope.
R2-D2 was present when Padmé gave birth to Leia and Luke, so he knew Luke was Anakin's son – but what he didn't know was that Anakin became Darth Vader. In addition to that, Anakin's fall was surely a painful event in R2-D2's life, one that he definitely wouldn't like to remember or even talk about.
At first, Ahsoka has no idea that Anakin Skywalker and Darth Vader are one and the same. She discovers the truth in Star Wars Rebels when she encounters the Sith Lord in a space battle. What she senses is so shocking to her that she passes out.
EVERY Person That Knew Darth Vader Was Anakin Skywalker - Star Wars Explained
Did Yoda know Darth Vader was Anakin?
Return of the Jedi establishes that Yoda was aware that Anakin Skywalker had fallen to the dark side and become Darth Vader. When questioned by Luke Skywalker, he confided that Anakin was Darth Vader. Later, Obi-Wan Kenobi's Force ghost confirmed that Anakin had indeed fallen to the dark side and become Darth Vader.
C3PO was clearly created from some sort of kit or existing prototype since every protocol droid aside from coloring looks the same. He didn't recognize him because again, they all look the same & it was decades until he saw him again. There was no reason to believe he or R2 even existed anymore.
The sequence calls back to a similar scene in Revenge of the Sith, when Bail Organa orders Threepio's memory be erased to prevent him from sharing information about Anakin Skywalker's fall to the dark side.
Maybe R2-D2 didn't know Darth Vader was Luke's father because he didn't see Palpatine christening him Vader, or maybe he believed Anakin was dead because even Obi-Wan didn't know Anakin was alive.
It was during his viewing of the hologram that Obi-Wan knew Darth Vader was Anakin. This is because Sidious said, “Henceforth, you shall be known as Darth… Vader”.
Owen Lars was a young adult when his father Cliegg married Shmi Skywalker, a Mos Espa slave he'd purchased and then freed. After Tusken Raiders kidnapped Owen's stepmother, a Jedi Padawan arrived in search of Shmi. This was Shmi's son Anakin, the stepbrother Owen had wondered if he'd ever meet.
Qui-Gon Jinn, who is considered a maverick Jedi Master by his colleagues, might have been able to keep Anakin on the path of the Jedi, had he not been killed by Darth Maul. Star Wars' Qui-Gon Jinn would have been the ideal mentor for the young Anakin.
And while his warnings don't work, at the very least, it shows that Maul became aware of Anakin and what he would soon become. With the rise of the Empire, it's likely Maul caught on to Vader's existence pretty quickly.
aware that Anakin had become the Sith Lord Darth Vader. Qui gon felt responsible because it was his dying wish. that Anakin betrayed in the ways of the Force. As the years went by, Qui Gon pushed himself to emerge physically as a spirit.
Leia's Force abilities and her lack of awareness of her true identity also contributed to Vader's inability to sense their familial connection. Vader's denial of Anakin Skywalker's legacy and his fear of getting hurt again prevented him from realizing the truth about his children until later in the original trilogy.
Since Obi-Wan and Anakin often fought together, Obi-Wan was friends with R2-D2 as well. This means that although R2-D2 might not have immediately recognized Obi-Wan on Tatooine due to his age, Obi-Wan should have recognized the droid.
Darth Vader DEFINITELY knows he's Anakin.. but it's something he HATES about himself. He's constantly haunted by Anakin's memories, but he does his best to “kill" that part of him. He WANTS them to be different people, in his mind he killed Anakin and rose as something stronger. However he's always aware of his past.
When Anakin fell to the dark side and became Darth Vader, Yoda was saddened, but firmly believed he was beyond redemption and forgiveness, and ordered Obi-Wan to hunt down and kill him. Even as a Force spirit, Yoda continued to believe that Vader was irredeemable and there was no good left in him.
In the material around the film from the Legends timeline, it's established that by the end of Star Wars: Episode III - Revenge of the Sith, Kenobi was one of the characters who knew Anakin's Sith name was Darth Vader. However, what he didn't know was that he was still alive after Mustafar.
Darth Vader didn't learn he had a daughter until Return of the Jedi, when he stood before Emperor Palpatine. The Emperor's power probed Luke's mind, attempting to goad him to fall to the dark side, and he discovered Leia's existence. "Sister," the Emperor taunted.
