While the final season of Game of Thrones has focused on the Great War (against the Night King’s undead army) and the Last War (against Cersei Lannister), neither of those conflicts can compare to the War of the Five Kings, which dominated the middle of the series run. The war tore Westeros apart, changing the political landscape of the Seven Kingdoms irrevocably, and destabilizing the region before the dead and the dragons arrived. It was a storm of turning points, but none were more important than the unexpected death of the first of the five kings, Renly Baratheon.
Granted, all five of the kings died, and most of them died quite a few seasons ago, so it’s understandable if you need a refresher. After the death of King Robert Baratheon, his “son” Joffrey Baratheon took the Iron Throne, but the gossip of Joffrey’s true parentage had already spread. The older of Robert’s two brothers, Stannis, asserted that the Throne rightfully belonged to him, as he was next in the succession line once it was determined that Joffrey and Tommen were illegitimate. However, Renly, Robert’s youngest brother and the Lord of Storm's End, also made a claim to the Throne despite Stannis’s rightful claim.
Meanwhile, Robb Stark and Balon Greyjoy were both attempting rebellions.
Of all the kings vying for victory, Renly’s claim was the weakest. Joffrey could at least claim the Throne under the guise that he actually was Robert’s blood heir, and Stannis could claim he was next in line after Robert. But, Renly was nakedly attempting to leapfrog Stannis to take the Throne for himself. The justification wasn’t there, which is a shame because Renly just might have been the best person for the job.
Renly wasn’t perfect. Sure, he boasted the full support and might of the Tyrells and their army, but his fighters were all, as Catelyn Stark noted, “knights of summer.” Renly was popular and good at talking the talk, but he might not have been the strongest leader Westeros had ever had. Even so, he had popular support and was arguably the favorite to win the war, based on the superior numbers of the Tyrell army.
Before his untimely death, Renly was even considering making some sort of agreement with Robb Stark’s forces. What, exactly, this would have looked like is unclear, but it’s possible that the Young Wolf would have been allowed to rule a free North, in exchange for helping Renly take the Iron Throne.
That would have changed everything, but it didn’t happen. Instead, Stannis used the darkest magic we’ve ever seen on the show to impregnate Melisandre with a shadow baby. That shadow assassinated Renly, a nasty bit of kinslaying and kingslaying in one.
For first-time viewers back in 2012, when the episode “The Ghost of Harrenhal” first aired, this was shocking. This marked the first and most overt time that magic influenced the mundane in Westeros; a war between men was averted because of a living shadow powered by a dark god of fire. Up until this point, the supernatural aspects of the show were either way up north — up at the Wall or inside of Bran’s head — or over in Essos with Daenerys and her dragons. But, suddenly, larger forces were altering the course of history. In retrospect, this is the moment when Game of Thrones transitioned from realpolitik to surrealpolitik, though there was still a healthy balance back then.
What this murderous shadow meant for Westeros, though, was the quick elimination of one-fifth of the War of the Five Kings. Renly’s death and the dissolution of his forces spared Stannis from what looked to be a losing battle against his brother. On the other hand, it also handed him a loss further down the line. Without Renly, the Tyrells instead join forces with Joffrey, and their army is the only thing that stops Stannis from taking King’s Landing.
Because Renly died, there was no alliance between the rebellious North and the Crown. Because Renly died, Brienne of Tarth pledged loyalty to Cat Stark, setting her on a road that would take her to Jaime and kickstart his redemption. Because Renly died, the Tyrells joined Joffrey’s side, sowing the seeds of political intrigue and Joffrey’s eventual death at Olenna Tyrell’s poisoned hand. Because Renly died, Stannis couldn’t take King’s Landing, so he instead saves the day during the Battle of Castle Black — and he fell deeper into the Red Woman’s spell, eventually sealing his own doom.
Even more than the Red Wedding, which fans remember because it was more shocking and had a higher body count, Renly’s assassination was the biggest event of the War of the Five Kings — utterly upending a conflict that was already upending a continent.