Regulus Black

"Fight, Fight for my master, the defender of the House elves. Fight for brave Regulus!"

- Kreacher

Regulus Arcturus Black (1961 - 1979) was the son of Orion and Walburga Black and the younger brother of Sirius Black, Harry Potter's godfather. According to Sirius, he had joined Lord Voldemort's Death Eaters, then panicked at the seriousness of what he was asked to do, and tried to back out.

Regulus was sorted into Slytherin House when he began school. At some point he was accepted onto his house's Quidditch team and was photographed with the team. Harry Potter finds this photograph many years later and says that Regulus played Seeker, based on his position in the seating.

Life and Times
"He was murdered by Voldemort. Or on Voldemort's orders, more likely, I doubt Regulus was ever important enough to be killed by Voldemort in person."

- Sirius Black Sirius noted that Regulus was exactly the opposite to himself, in the eyes of his parents. Although Sirius was the older son, he disagreed totally with the traditional views of his family, and as a result left home while still at school. On the other hand, his parents regarded Regulus as an ideal son. Voldemort was seen as standing for the cause of Pure-blood supremacy over other wizards and Muggles, and this idea was firmly supported by the Blacks. As a result, they generally approved when Regulus became a Death Eater. However, unlike other members of their wider family, Orion and Walburga were not themselves Death Eaters.

Regulus' cousin Bellatrix Lestrange is shocked and infuriated in 1996 when Harry Potter tells her that Voldemort is a half-blood. It may be that Regulus, with similar beliefs to his cousin, was similarly shocked to discover that he had dedicated himself to the cause of a halfblood becoming ruler of the wizarding world. Regulus becoming hunted by Voldemort is consistent with his father's concern about security, his mother's comments and the coincidence in the death years of himself and his father. As Voldemort never read Regulus' note nor ever discovered (prior to 1998) that the Hocrux was stolen, it is possible that he believed Regulus to have escaped him.

In interviews following the final book, J. K. Rowling has said that it was Voldemort's mistreatment and intention to kill Kreacher that first turned Regulus against the Dark Lord.

In 1997, it is revealed to Harry that he had learned of the Horcruxes before "leaving" the Death Eaters. He and Kreacher then traveled to the cave, where Regulus drank the potion, and Kreacher switched the lockets. Kreacher, still following Regulus orders, sailed away, watching horrified as Regulus was dragged beneath the lake by the Inferi.

After hearing Kreacher's story, Harry gives him the replica locket that had been left in the potion. Kreacher then becomes much friendlier to Harry.

During the Battle of Hogwarts Kreacher rallies the House elves, and leads them, telling them to fight for both Harry Potter and Regulus.

Horcrux Connection
It was revealed in 1997 that R.A.B. was in fact Regulus Arcturus Black in a tale told by Kreacher, the house elf that served the Black family. It was revealed that the cave and its chamber had always been there and that the potion had been prepared prior to Voldemort's hiding of Salazar Slytherin's Locket due to Kreacher being forced to drink it by Voldemort, who refilled the basin with the potion upon placing the locket inside it. However, Kreacher told Regulus, who then after a time went to get the locket and give it to Kreacher to destroy before being taken under the dark water of the underground lake by the Inferi.

Derivation of name
The Black family seems to have a tradition of naming its members after stars and constellations. In Latin regulus means "little king" and was one term for a basilisk. As a name it has also been applied to the star Alpha Leonis, which is situated at the heart of the lion in the constellation of Leo. Regulus was also the family name of a Roman general, Marcus Atilius Regulus, who was known for his honour and self-sacrifice. Arcturus is also a star, in the constellation Boötes. It is derived from Ancient Greek meaning "bear guardian".