Disclaimer: I make no money from any of this, all characters are property of J K Rowling
Prologue – The Beginning
The war against Voldemort came to an end before it had even begun. The self-proclaimed Lord Voldemort, Dark Lord of the time, had lured Harry Potter to the Ministry of Magic down into the Department of Mysteries under the pretext of holding Sirius Black prisoner. It was there, right in the middle of the atrium in the ministry that you-know-who was defeated by fifteen year-old Harry Potter, witnessed by several high ranking ministry officials, dragged there at Dumbledore's behest, all of whom had not believed Harry's claims from the previous year.
Since the return of Voldemort the previous summer the Order of the Phoenix had been working on several jobs. Their first job had been keeping a prophesy relating to Harry Potter and Voldemort, that was down in the department of mysteries, safe from the dark lord and his forces. Their other job had been looking into ways of defeating Voldemort,
Ever since Lucius Malfoy had given Ginny Weasley Tom Riddle's diary in her first year of Hogwarts, and the opening of the Chamber of Secrets, Dumbledore had known the source of Voldemort's immortality; that which had stopped him from dying all those years ago when he first faced the baby Harry Potter. He had spent the intervening years searching for the other similar artefacts that Voldemort had created. These artefacts, called Horcruxes, contained pieces of Voldemort's soul, which meant that even if his body was destroyed, his soul would remain upon this plane.
Dumbledore had spent his exile from Hogwarts, during Delores Umbridge's reign, hunting down and destroying the horcruxes he had been able to locate already. An old family heirloom of a ring hidden in an old shack, not far from the old Riddle house was the first horcrux to be destroyed with the assistance of Severus Snape as there was a very dark curse placed on it, which would have killed the wearer had anyone put it on.
The second was a locket that had been hidden inside Grimmauld Place that Kreacher had reluctantly handed over after the locket belonging to Regulus Black had been discovered inside a cave on the Cornish coast, which had been Voldemort's original hiding place for the locket of Salazar Slytherin. Sirius had been quite overcome to find out his brother had had a change of heart about Voldemort only to meet his demise at the hands of his destruction.
The lost diadem of Ravenclaw had been hidden within Hogwarts itself. Filius Flitwick, as the Ravenclaw head of house, had been sent into the Room of Hidden Things to retrieve it. He came out babbling about how great it was to hold such an amazing piece of history in his hands and what a shame it was that it would have to be destroyed, while somehow managing not to alert Umbridge into what he was doing.
Nymphadora Tonks had descended into the Gringotts vault of Bellatrix Lestrange, the only person who was able to other than the Lestranges themselves as she was both an auror and a family member, to retrieve the Cup belonging to the founder of her house: Hufflepuff.
The final Horcrux that they needed to destroy had been Nagini, Voldemort's snake, and had been located slithering around the ministry at the same time the six children, Harry Potter and his friends, were seeking out Sirius Black; one well-placed chop with the sword of Gryffindor had severed her head from her body destroying the horcrux.
It was after this that Voldemort was defeated; Bellatrix Lestrange having just killed Sirius Black fled from the veil room causing Harry to chase after her, determined to avenge his godfather's death, when it happened. Voldemort had made his appearance and had tried to kill Harry, if it had not been for Dumbledore's arrival and protection it was likely Harry would have died. A spectacular battle was then fought between Dumbledore and Voldemort but it was during that fight that Voldemort possessed Harry, tempting Dumbledore to try and sacrifice Harry in order to destroy him. However, Voldemort had been unprepared for the depth of love Harry felt within him; for his family that had been killed, for his friends that stood by him and the wizarding world that depended on him, that it had destroyed Voldemort and shattered the link between the two of them. Dumbledore theorised that Harry's love had destroyed a piece of Voldemort's soul inside of him that had attached itself upon Voldemort's first demise; the magical backlash had been so powerful that it had destroyed the last remaining piece of Voldemort's soul, inside the man himself
The backlash of magic had critically injured Harry and had knocked him unconscious. Unfortunately, Dumbledore had been preoccupied in dealing with the aftermath of Voldemort's demise with the Minister for Magic and his lackey's that he had failed to notice what had happened to Harry. It had fallen to one Lucius Malfoy, who had escaped from the Death Chamber, where Sirius Black had perished, and had been watching all that had occurred in the shadows, to pick up the fallen hero and transport him back to Hogwarts where he could be healed away from prying eyes and vengeful Death Eaters.
It was a week later, when Harry was still in the hospital wing, that a letter was sent out to him from Gringotts; this would set events in motion that had been hidden for nearly sixteen years, and they all revolved around Harry Potter. They would determine the young wizard's future and what choices he made.