Sirius Black

Sirius Black was first mentioned briefly in Harry Potter and the Philosopher's Stone as a wizard who lent Hagrid a flying motorcycle shortly after Voldemort killed James and Lily Potter. His character becomes prominent in Harry Potter and the Prisoner of Azkaban, where he is the eponymous prisoner.

Sirius Black is one of the last people born to the House of Black, a prominent family of pure-blood wizards and witches. Known members of the family include his cousins, Narcissa Black, who married Lucius Malfoy and gave birth to Draco Malfoy; Andromeda Black, who married Ted Tonks and gave birth to Nymphadora Tonks; Bellatrix Black, who married Rodolphus Lestrange; and his brother Regulus Black, who, according to Sirius, tried to leave the Death Eaters and was killed on Lord Voldemort's orders. A popular theory says that Regulus tried to destroy one of the horcruxes that Voldemort produced to secure his immortality; see discussion in the article on R.A.B.

Sirius Black was best friends with James Potter, Harry's father, and was also friends with Remus Lupin and Peter Pettigrew. When they discovered that Lupin was a werewolf, his friends helped him by secretly becoming Animagi because Lupin was not compelled to attack non-humans. Sirius's Animagus form was that of a dog and his nickname was therefore "Padfoot".

At the age of sixteen, Sirius ran away from home to live with the Potter family, disgracing his family and prompting the removal of his name from the Black family tree tapestry (a fate shared by any Black family member his parents didn't like).

When James married Lily Evans, Sirius was his best man at the wedding and later became Harry's godfather. By making him godfather, James and Lily had appointed Sirius as Harry's guardian in case anything happened to them.

Sirius's family sympathised with Lord Voldemort's desires to cleanse the Wizarding world of non-purebloods and his younger brother Regulus joined the Death Eaters.

When James and Lily went into hiding from Lord Voldemort, they wanted to make Sirius their Secret-Keeper, but Sirius convinced them that Peter Pettigrew would be a better choice because no one would suspect Peter of being trusted with that task. However, Pettigrew was a traitor, and he betrayed the Potters to Voldemort. Pettigrew faked his own death and successfully framed Sirius for the Potters' deaths and for his own "murder". This led to accusations of Sirius's involvement in the murder of thirteen people (twelve muggles and Pettigrew) and the Potters and his subsequent incarceration at Azkaban. Sirius was given no trial — his guilt was assumed so completely by everyone that no trial was considered necessary and Barty Crouch, who gave the order, was ruthless in his pursuit of justice.

During the course of events described in Harry Potter and the Prisoner of Azkaban, Sirius escapes from Azkaban after learning that Pettigrew is still alive and at large. After some confusion, Harry comes to realize that Sirius is on the side of good, and begins to see his godfather as the father he never had. After Sirius is recaptured at Hogwarts, Harry helps him escape with Buckbeak, a hippogriff which has also been unfairly condemned.

As a fugitive, Sirius could communicate with Harry only sporadically. When Harry, Ron, and Hermione communicate with him in the fourth and fifth books, they call him "Snuffles" and pretend that he is a friendly stray dog. Harry continues to rely on Sirius as a father figure, and often turns to him in times of great need.

During the events described in Harry Potter and the Order of the Phoenix, Sirius lends his family home for use as the headquarters of the Order of the Phoenix. He is effectively confined there due to the manhunt for him, even though Kingsley Shacklebolt, the Auror assigned to his case, is also a member of the Order but especially because Pettigrew has now informed his master Lord Voldemort of Sirius disguise as a dog. When he leaves for a short time to see Harry to the train station on his journey to Hogwarts School of Witchcraft and Wizardry, his Animagus form may have been recognised by Draco or Lucius Malfoy. Despite this, Sirius makes numerous attempts to contact Harry through the Floo Network, a system by which wizards and witches can communicate through fire, which is eventually monitored by the Ministry of Magic and Dolores Umbridge.

Lord Voldemort uses his growing power to influence Harry's mind, making him believe that Sirius is being held captive in the Department of Mysteries. In the ensuing battle Sirius is hit by a spell from Bellatrix Lestrange, his own cousin, sending him falling through a gate between the living and the dead. Master wizard Albus Dumbledore, fellow Marauder Remus Lupin and ghost Nearly Headless Nick all state that no living being could pass through the barrier without being killed. It is not known with absolute certainty whether he is really dead, he may be in the veil but with a possibility of return. J K Rowling was asked if he was really dead, and replied suggesting that she did not believe in characters miraculously recovering.

The opening chapter of the sixth book mentions that Sirius has been cleared of all criminal charges against him following his death, and that a formal inquiry will be made into the circumstances of his wrongful arrest and incarceration. The outcome of this inquiry and any resulting actions are currently not known.

Because of his popularity with fans and his untimely death, Sirius Black can be considered the Mercutio of the Harry Potter series.

Sirius left all his property to Harry. Independently wealthy and having no great love for the place, Harry immediately gave Grimmauld Place to the Order's use. Kreacher the house-elf was now forced to serve him, which did nothing to help the elf's disposition, and was sent to help at the Hogwarts kitchens. Buckbeak passed into Hagrid's care. The whereabouts of the motorcycle are unknown.

It should be noted that had Sirius died without having made a will his possessions would have passed to his murderess, Bellatrix Lestrange (née Black), as his cousin and next-of-kin. Sirius's property would have been passed to his brother Regulus, but the younger Black is believed to have predeceased him, and neither Sirius nor Regulus had children in possession of the Black family name. Initially unsure of who inherited the property, Albus Dumbledore had Harry give Kreacher an order; Kreacher obeyed, showing that Sirius' will was able to break the Black family enchantments on the property.

Sirius was a rather tragic figure. His life was not the happiest and never gave him time to properly mature emotionally, which caused him to remain somewhat of a loose cannon all his days. In his Hogwarts days, he was a brash but apparently quite normal youth, but when differences in opinion between him and the rest of his family broke contact altogether, he was left craving the friendship and acceptance of his peers. This he found, which made him fiercely loyal to the Marauders, the closest people he had left. At this point he was (later on self-admittedly) an idiot. Arrogant and with a devil-may-care attitude, he was a bully to those outside his circle of friends. He would later come to regret this, but not enough to seek amends with Snape, his prime target.

After leaving school, the newly adult Sirius joined the Order of the Phoenix to take up the fight against Voldemort, putting himself into a high-stress environment where trust was scarce. This proved manageable until fellow Marauder Peter Pettigrew betrayed James and Lily Potter, causing their deaths, after Sirius had unwittingly put him in the perfect position to do so. When Pettigrew framed Sirius for his own murder, too, it was entirely too much to bear, and the wound would last for life.

That Sirius survived twelve years in Azkaban at all is remarkable. That he was, even in part, salvageable after them is awe-inspiring. For over a decade he was capable of nothing but trying to hold on to vestiges of his sanity. His dog-form gave him respite from the Dementor's presence, his guilt over James and Lily gnawed at him, and his desire for revenge became an obsession. On escape, he had been greatly tainted by the prison. For the following year, he was directed by the fixation to commit the crime he had been convicted of, wild and alone.

It was only when he had his target at wandpoint that things took an up-turn. He was re-united with Lupin, but more importantly also with his godson, Harry. It was the latter who gave him a reason to give up on committing murder. The two formed a strong bond quickly, and though he was forced back on the lam Sirius could now allow himself to heal. Though clearly still Azkaban-marked, he fast started to again resemble an ordinary person. He never had time to properly become an adult, though, and though his desire to protect Harry helped, he remained foolhardy. He desired a brotherly figure while Harry did the same for a parental one, and Sirius occasionally seemed to have trouble distinguishing him from James. When Voldemort rose again he was forced into his family's home, which he hated, to avoid capture. Though this did wonders for his social life (he gained one), it made him cross and morose, and increasingly frustrated as he felt he was being kept from doing his part in the war. He was unable to overcome his feud with Snape or his loathing for Kreacher, the demented house-elf of 12 Grimmauld Place. It is not surprising that when the Order sent an emergency team to rescue Harry and the gang from the Department of Mysteries, Sirius jumped at the opportunity. The Death Eaters were faced with a man who fought with exuberance right until he was killed by falling through a black curtain (in the Department of Mysteries) while duelling with Bellatrix Lestrange.

Sirius never had a family to continue the family name of Black, therefore, with his death, the Black family came to an end.

As with many Rowling characters, Sirius's name reveals part of his nature. "Sirius Black" is a pun on the fact that Sirius can turn into a giant black dog; Sirius is the name of a star (the brightest one in the sky) which can be found in the constellation Canis Major (the big dog). The star Sirius was called "dog's star" by some ancient cultures such as the Egyptians. Most (but not all) of Sirius's family is likewise named after stars (Bellatrix is in the constellation of Orion; Regulus is in Leo. Andromeda is a constellation in the northern hemisphere, as is Draco). "Black" is an obvious reference to the colour of Sirius's canine alter-ego: black.

Ref: Wikipedia
http://en.wikipedia.org/wiki/Sirius_Black