283 AC

The Battle of the Trident decided the battle. The Usurper's warhammer struck a grave blow to the prince but it was in the end Rhaegar that stood victorious. This ended Robert's Rebellion but the Mad King could not remain on the Iron Throne. Rhaegar and his troops rode South, where they met the Lannister forces. Against Aerys' orders the gates were opened, and the Mad King attempted to burn down the city but Jaime Lannister prevented that by slaying his king. His wife and mother of his two children were safe, but when he finally reached Dorne where Lyanna was kept safe, he discovered that his second wife had died in childbirth.

The boy was taken with him to the capitol and Rhaegar began his reign. Over many years he mended the relationships between the kingdoms and Great Houses that had led to the Rebellion, the consequences of his father's reign. But though he had survived the war, the wounds had always lingered. Rhaegar was a great king but his health was always an issue and no matter what the maesters did, at best it seemed like they could prolong his life.

The King had to prepare his heir to finish his life's work, but would prince Aegon be worthy? Even in his early years it seemed as if there was too much of his grandfather in him. There were those that feared another reign of the Mad King, and there were those that flocked to the prince as they sought to exploit this. And far from the capitol was the threat of another Mad Prince, this one older. Prince Viserys had never forgiven his brother and always saw Rhaegar's health as an opportunity. His ambition and madness fueled by the supporters that whisper into his ear.

Both Mad Princes have intentions to take their sisters, Rhaenys by Aegon and Daenerys by Viserys, and make their claim once Rhaegar passes. Though both seem to grew restless and willing to help speed things along.
Now summer has ended and we seem in for a bloody fall, Rhaegar is doing his best to prevent another war and to help keep the peace in the realm. Ignoring the rumors about his son and trying to shape him into a worthy heir. But the tension in King's Landing made him decide to sent his second son away. For his own safety and for the good of the realm, to prevent yet another faction forming around another claimant. A marriage pact was to keep the boy safe and away from the game of thrones.

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It could go a lot of directions, the prince could go South to Dorne to become Arianne's betrothed. Or perhaps to Highgarden to marry Margaery as the Tyrell's hope to influence the royal family to combat their Dornish rivals. Or perhaps to the North? The Westerlands?
For this I really hoped to a classical betrothal story. Characters with their own flaws and ambitions thrust into an arranged marriage, meanwhile tension and war looms over them.