When Aegon the Dragon landed in what is now King's Landing, the seven kingdoms were exactly that, seven completely separate kingdoms ruled by seven separate kings. Each with their own agenda, and dreams of dynastic longevity. They all quaffed at the Dragon's offer of alliances, seeing the man as nothing more than a foreign upstart who would not stand a chance against the might of the Storm King or the Ironborn, let alone the other kingdoms. They were proven wrong. Aegon and his sister wives- Visenya and Rhaenys- quickly gained the support and fealty of many of the lords of the crownlands, and soon began work on establishing themselves as a force within Westeros.
Of course the rest is known throughout the country as history. Aegon sent his sister wife Visenya to the Vale along with his cousin of House Velaryon and a fleet of ships, though his cousin and the fleet burnt at Gulltown, Visenya flying on her dragon Vhagar managed to get the boy king of the Vale and his mother to bend the knee. Aegon had also sent his sister wife and his bastard brother to the Stormlands to earn the fealty of King Argillac, the man refused to surrender and so was slain in single combat by Orys Baratheon- Aegon's right hand man and bastard brother-. Orys would later go onto marry the Storm King's daughter and adopt her words and sigil for his own, and would found the House Baratheon.
Aegon then marched his men to Harrenhal, where the prideful and foolish Harren the Black refused to surrender. Aegon in a showing of true Targaryen steel unleashed all three of his dragons on the fortress mad King Harren had built- Harrenhal- the castle was left a ruined cinder of its former glory, Harren and his line ended that very day. Lordship of the Riverlands given to Edmyn Tully, Lord of Riverrun and the first riverlord to bend the knee to Aegon the Dragon.
The Field of Fire would be the only time all three Targaryen dragons were ever engaged in full on combat. A rout seemed to be occurring as the armies of Loren Lannister and Mern Gardener crushed and ran through the Targaryen soldiers- all of whom were either of certain or uncertain loyalty- it seemed the Dragon would be tamed, and that Aegon's dream of ruling over Westeros would remain just that. That was until the dragons came in all their majesty to cast a shadow over the earth, fire was unleashed and the armies of the Rock and the Reach were burnt to a cinder. House Gardener died with its king and his heirs, House Lannister survived, Loren Lannister becoming the first Lord of Casterly Rock and Warden of the West. House Tyrell became Lords of the Reach and Wardens of the South for their lord's good sense in bowing to Aegon the Dragon.
The North and Dorne still remained the only obstacles to the conqueror's dream of uniting Westeros under one ruler, Torrhen Stark marched with a great host down the neck and camped on the banks of the Red Fork. Seeing the great host and the three dragons that the Conqueror had, Torrhen Stark put the safety of his land and people before his own pride and honour and bent the knee to the Conqueror becoming Lord of Winterfell and Warden of the North. Dorne was a trickier beast to tame, and in fact when Aegon was crowned in Oldtown alongside his sister-wives, Dorne was not part of the assembled kingdoms that cheered as the Dragon was made King over all of Westeros. For though Aegon's title proclaimed him King of the Seven Kingdoms, Dorne through stubborn determination remained independent.
Aegon let the matter rest for the remainder of his reign, instead he focussed on having a suitable keep made and built for the royal family to reside in, as well as ensuring that his hold on the six kingdoms he was technically king of was solid and secure. The faith, though they grumbled privately over the incestuous nature of the new King's marriages dared not bring the wrath of the Dragon upon themselves, and so dealt in compliance with the King's wishes.
They kept an eye on the Dragon's sons though, weak Aenys born from Rhaenys, who seemed to be destined to inherit born in the Third Year after his father's landing, shared the Targaryen features of both his parents, though in attitude he seemed to take after his mother Rhaenys. He preferred luxuries and the fanciful things of court, never truly seeming to care for the martial side of things. Aegon the Dragon had three more children by Rhaenys, all of them girls. Daenys, Velena and Eleana were their name, though in breaking with Valyrian Tradition Aegon decided not marry his eldest son to his eldest daughter and instead married Aenys to Edmyn Tully's daughter Catelyn. Their children would be known as Jaehaerys and Alysanne. Daenys was married to Aegon's second son Maegor, though she died in childbirth giving birth to a stillborn girl. Velena was married to Orys and Argella's son Robert. Eleana was then married to Maegor and that union produced three children, two girls and a boy.
Maegor born during the eighth year after his father's landing grew to be a fierce some warrior and man. Considered a loner and cruel by some for his more melancholic choices, to his family he was known as caring and compassionate and fiercely loyal. Upon his wife's death from childbirth he remained at her side- standing vigil- for more than seven days, his father had to forcibly move him from the sept where Daenys was placed. Maegor's marriage to his second wife Eleana was a happy albeit short one, they were married during the last year of Aegon the Dragon's reign and had three children together. Twin girls whom they named Visenya and Rhaenys after Maegor and Eleana's mothers, and then in the first year of their brother Aenys's rule a son was born to them whom they named Vaegyl.
The faith who had kept a rather close eye on the children of the dragon, waiting for the most opportune moment to pounce, saw the opportunity when Aegon the Dragon died from old age in the 37 th year after his landing. Aenys ascended the throne, sickly and weak, and the Faith rebelled, denouncing his claim to the throne as a product of incest, they called for all those who were pious and true to their devotion to the seven to rebel with them. Bloody revolts soon followed, attempts were made on the Royal family's life, and some of those attempts failed, some succeeded. Eleana Targaryen wife to Maegor was killed by a arrow meant for her husband- Aenys' hand- driving Maegor from being an angry man, to one filled with cold hatred toward the faith and all they represented. The revolts of the minor lords were ended when Maegor flew on Balerion the Black Dread, and forcibly ensured that the Arryns of Gulltown ended their treachery- they were all executed and hung from the walls of the Eyrie- The minor lords stopped rebelling then, but still the faith continued. It has been rumoured though never expressly proven or stated that the High Septon may have had King Aenys' drink poisoned, and that it was this poison that killed the king.
With there still being turmoil in the land, and with his brother's children still being very young, Maegor ascended the throne and set about trying to put the wrongs to right. At the urging of his hand and loyal servant Gerold Westerling, Maegor married the man's daughter Jeyne, and with her sired three children, Aegon, Daemon and Laecareys. Despite this, the rebellions still continued, and upon his death in 48 A.L. the Faith seemed to be winning. With there being contentions over the issue of succession, Jaehaerys Targaryen son of Aenys I assumed the regency of his cousin Vaegyl and began negotiating for peace.
This tale begins in the 56 th year after Aegon's Landing. Jaehaerys and the small council- including Gerold Westerling - are sat planning their next move, with Vaegyl about to reach manhood, and the faith still rebelling decisions needed to be made, and quickly. Unbeknownst to Jaehaerys and half the small council, Gerold Westerling with the aid of Ser Tybolt Lannister was already making overtures to seat his grandson Aegon on the Iron Throne.