In the ASOIAF series Robert's Rebellion is arguably the most important event prior to the first book. The civil war which brought down the 300 year old Targaryen Dynasty laid the foundation for the entire book series and show. Without this successful insurrection, nearly every character in the series would be in a different place.
But what if the rebellion's climactic battle, The Trident, had gone a different route? What if in their duel in the waters, Robert was slain by Rhaegar and the rebel forces suffered a shattering defeat? How would the Seven Kingdoms be different?
There are a myriad of ways that the Rebellion could have ended with a Targaryen victory. For my purposes I'll be looking at a different outcome for the Battle of Trident with all other events leading up to that point unchanged.
|A different man comes back from the Trident|
In this new scenario, Rhaegar leads the loyalist army into battle and confronts Robert one on one in the waters of the river. This time though, Robert misses his swing and Rhaegar dodges the fatal blow of the Usurper's warhammer. Rhaegar rebounds and puts his sword through Robert's antler helm killing him instantly.
Upon seeing their leader fall, the rebel army reacts in the same way that the loyalist army did in the cannon history at the death of Rhaegar. The Baratheon, Stark, Tully and Arryn forces scatter and their enemies are victorious.
A victory for the Targaryens at the Trident has very deep changes for the Kingdoms and for the characters of the series.
First, with the rebels clearly on the backfoot the loyalists are free to press their advantage and continue to march into the Riverlands. Neutral houses, seeing which way the wind is turning, declare for the Targaryens. The Freys, who in the cannon waited to send troops to the Trident after the battle is decided, join the Royal Army along with other Riverlords.
House Lannister, declares for the crown and sends their armies into the Riverlands to assist.
Meanwhile, in Storm's End the siege continues and the Tyrells eventually starve the garrison led by Stannis. The elder of Robert's two brothers is killed or captured while the youngest brother Renly is (for sure) taken hostage to ensure the loyalty of the Stormlands. With Robert gone, the Stormland forces in the Riverlands disintegrate leaving the Arryns, Starks and Tullys to try and mount a new defense.
The Mad King Falls
As revealed by Jaime in A Feast for Crows, Rhaegar stated before leaving for the Trident that he wanted to call a council after the battle was over. In his own words:
'When the battle's done I mean to call a council. Changes will be made. I meant to do it long ago, but ... well, it does no good to speak of roads not taken. We shall talk when I return.'
The council Rhaegar referred to is likely a council to remove his father, Mad King Aerys, from power. POV chapters from other characters in the books indicate that Rhaegar was disturbed by his father's madness and wanted to depose him in order to preserve the Kingdoms. The tourney at Harrenhal (where Rhaegar met Lyanna Stark) was believed by some in the books to have been a cover for a meeting between Rhaegar and supporters to plot Aery's overthrow. Aerys was tipped off, however, by his spymaster Varys. He attended the tournament and, as the story goes, the plot never hatched.
In this new scenario, Rhaegar takes advantage of his victory and finally calls the long delayed council. He gathers his strongest supporters and his father's closest enemies. This includes Aery's former estranged Hand and friend Tywin Lannister. In the cannon timeline, Tywin's friendship with Aerys was ruined by the Mad King's jealously and paranoia, with Tywin resigning his post. It's also recorded that during the defiance of Duskendale, Tywin openly talked about replacing Aerys with Rhaegar.
|At Rhaegar's council, Tywin becomes a crucial player.|
At the council, most likely held in the Riverlands (perhaps Harrenhal), Tywin and Rhaegar's allies back his coup against his father to spare the realm even more bloodshed.
Rhaegar leaves Barristan Selmy or another lord to lead part of the Royal Army in the Riverlands and continue the right against any remaining rebel forces. He and Tywin though take the lion's share of the army to King's Landing.
While Rhaegar may try to disguise this move, Aerys's paranoia, perhaps coupled with information from Varys, prevents him from accepting his son back into the capital. He keeps the gates of King's Landing shut and threatens to kill Rhaegar's wife and children (who are still in the Red Keep). The Mad King also has the caches of wildfire scattered around the city which he plans to use in this timeline as well.
Though the standoff continues for some time, the outcome probably remains very much the same as in the cannon-timeline.
Jaime Lannister remains the only Kingsguard in the Red Keep, since he was left behind before the battle. Though he is a Kingsguard, it's also established in the books that he had a close relationship with Rhaegar and that he is not above breaking vows for what he perceives as a greater good.
With that mind, it's possible that Jaime would, eventually see the writing on the wall and take it upon himself to spare the city and his father's forces.
The Mad King falls, most likely stabbed once more by Jaime.
King's Landing is spared being sacked or burned and Rhaegar becomes king.
With Rhaegar now King and his father gone, the new Targaryen monarch begins the process of bringing all seven kingdoms under his control.
With the Stormlands all but secured by the Tyrells, the Riverlands, the Vale and the North are the only three territories left uncontrolled by the new Dragon King.
|House Arryn, House Stark and House Tully form the backbone of the rebels|
Rhaegar would no doubt hear a number of different opinions from his small council on how to deal with these rebellious territories. While an all out military invasion of these lands would be possible, especially with the Royal Army intact, continuing the war would be problematic. Apart from the Riverlands, which have few natural barriers, the North and the Vale would prove difficult to invade and conquer by force.
The Vale is extremely mountainous while the North is huge (as large as all the other kingdoms combined). Though the forces of the Great Houses backing Rhaegar could mount invasions of these two kingdoms, the campaigns would cost a number of lives and could ultimately result in a war of attrition that might cause the loyalists to suffer burnout.
Therefore, Rhaegar's best course of action would be to negotiate the reentry of the North and the Vale into the Seven Kingdoms.
This might seem like an impossible task at first, especially when it comes to making amends with House Stark. After all, Rhaegar's absconding with Lyanna Stark was the flash that ignited the rebellion in the first place. How could Ned Stark (assuming he escaped the defeat at the Trident) or his brother Benjen (who would have become lord of Winterfell had Ned fallen) possibly make peace with the man who 'abducted' their sister? How could Ned, if he survived, have forgiven the man who in this alternate timeline, killed his best friend?
Well a negotiated peace, is actually not as crazy an outcome as you might think. In this alternate timeline, Rhaegar has two aces in his already stacked deck.
First, there's the fact that Rhaegar's dalliance with Lyanna, wasn't really what started the rebellion.
Sure, taking off with Robert's fiance was a dumb move. Whether you like the abduction narrative or the star crossed lover story, there's no doubt Rhaegar made a mistake when he rode away to Dorne with Lyanna. Yet it was the actions of Rhaegar's father, the Mad King, that actually set off the war.
|The Mad King burns Rickard Stark|
Brandon Stark, the heir to Winterfell, and Rickard Stark, (the Stark patriarch) were both executed when they approached Aerys seeking justice for what they saw as a slight on their family's honor. It's their deaths at the hands of Aerys, and his subsequent order for Jon Arryn to send him the heads of Ned and Robert, that kicked off the rebellion. Though negligent, Rhaegar had no direct responsibility for the war.
With his father now dead, in this alternate timeline, Rhaegar can argue that he actually avenged the Stark family by deposing his father and bringing the man responsible for Brandon and Rickard's deaths to justice. With the Mad King gone, the rebels no longer have a hated figure to rally against. Though Rhaegar is his father's son he's also well loved.
Despite being on the losing end of the war in the cannon-timeline, Rhaeagr is still widely praised even in death for his honor and noble character. Apart from Robert, everyone else who knew the prince personally remarks on how good a person he was and laments that he never got a chance to be King. Even Ned speaks well of him, despite having no apparent reason to.
Second, and maybe most importantly, Rhaegar has a Stark in his care. I don't mean Lyanna. Just like in the books, Lyanna dies at the Tower of Joy in her bed of blood. And she also gives birth to the boy we all know as Jon Snow. (Yes, there may be a half percentage chance that R + L does not equal J but at this point the show has almost certainly confirmed it).
|Unfortunately, Lyanna Stark still dies in childbirth.|
In this alternate version though, Jon is given a Targaryen name (I'll use the popular fan name Jaehaerys) and is taken back to his father by the three Kingsguards left to protect him and his mother in Dorne.
It's the revelation of this little boy's existence, more than anything else, that convinces either Ned or Benjen to submit to Rhaegar's rule. While the Starks may nurse strong grudges against Rhaegar for the rest of his life, they would still feel a strong devotion to Lyanna's son. Ned's code of honor and his dedication to family, would ultimately bring him to the table and back to submission to the Targaryens. While Benjen is not quite as honor bound as Ned is, we can safely assume that he would also submit.
Assuming the North is brought back to the fold the Vale and the Riverlands would then follow suit, seeing no purpose to continuing the fight. The Arryns remain in charge of the Vale and the Tullys, the Riverlands. Rhaegar lacks his father's penchant for cruelty and would most likely not seek any vengeance.
The Rule of Rhaegar
With the Kingdoms at peace, the reign of King Rhaegar truly begins. Though the rebellious lands are pacified, bitterness over the events of the rebellion would no doubt remain. Though their houses remain intact, the Baratheons and the Starks would have grudges against the throne. They, the Arryns and Tullys, as well as other large houses that supported Robert, would need to be kept in check. Children from those houses would stay in King's Landing, Dragonstone or in loyalist Great Houses, as hostages. The best candidates would be the heirs of these houses such as Robb, Renly, Robert Arryn and Edmure Tully. Renly, as the heir of Storm's End, would be an especially valuable captive to the new Targaryen king.
|Prince Jaehaerys Targaryen|