A Knight of the Seven Kingdoms has reached the end of its first season, and it left a whole lot of emotions in its wake. "The Morrow" is a quiet season finale, which sees our venerable hedge knight Ser Duncan the Tall (Peter Claffey) and his squire Egg (Dexter Sol Ansell) finally take their leave of Ashford Meadow following the death of Baelor Targaryen (Bertie Carvel).
Things will never be the same for Westeros after that fateful tourney. Baelor was the heir to the Iron Throne as well as the Hand of the King to his father, King Daeron II. He had been training his entire life to take up the mantle of kingship, and is widely considered one of the most qualified rulers-in-waiting in Westerosi history. With his death, everything is thrown into doubt.
It's all the more painful for the fact that Baelor's death was an accident; during the trial of seven, his brother Maekar (Sam Spruell) hit him too hard with a mace, crushing in the back of his head. There was never any animosity between the brothers before that trial, and in the season finale, it's easy to see how torn up Maekar is about the sudden death of his older sibling.
With Baelor dead, it begets an important question: who is next in line to the Iron Throne? Is it Maekar himself?
While the show doesn't linger on these details before sending Dunk and Egg on their next adventure, there are certainly answers to be found in George R.R. Martin's book The World of Ice and Fire, which is a sort of official encyclopedia for Westeros.
Who becomes King of the Seven Kingdoms after Baelor dies?
In the immediate aftermath of Baelor's death, his father, Daeron II remains king for around a year longer. But then Westeros is hit with a sudden plague known as the Great Spring Sickness, which claims the life of Daeron the Good, as well as both of Baelor's sons, Valarr and Matarys. This effectively wipes out Baelor's lineage as Daeron's eldest, removing it from the line of succession.
King Daeron and Queen Myriah Martell have four sons total. In order of their age, there's Baelor, Aerys, Rhaegel, and Maekar. So even after Baelor and his entire line gone, Maekar is still a ways down the line of succession. Both Aerys and Rhaegal were mentioned in A Knight of the Seven Kingdoms Episode 2, so we know the show kept the full family tree intact.
Following the death of Daeron, his second-oldest son, Aerys, is crowned king. However, Aerys is an ineffectual ruler, and more interested in pursuing bookish pursuits than fathering an heir or overseeing the realm. He largely abdicates his responsibilities to his Hand of the King, a Targaryen bastard named Bloodraven. He is the ruler of the Seven Kingdoms during the second Tales of Dunk and Egg story, "The Sworn Sword," which forms the basis for A Knight of the Seven Kingdoms season 2.
Around six years into Aerys' reign, his brother Rhaegel — who had been his heir — chokes on a lamprey pie and dies. Aerys then names Rhaegael's son, Aelor, as heir, but he also dies in a freak accident. Then he names Aelor's twin daughter Aelora as heir, but she also dies, committing suicide following an attack by three masked individuals at a ball known as the Rat, the Hawk, and the Pig. Rhaegel's youngest daughter Daenora is married to none other than Aerion Brightflame, and as Aerion is Maekar's child, that means Maekar is ahead of him in the line of succession.
As such, following the death of Aelenor and Aelenora, Maekar Targaryen is finally named heir to the Iron Throne. When Aerys dies of natural causes a few years later, Maekar finally ascends the Iron Throne as King of the Seven Kingdoms.
Parsing the Targaryen family tree is always a complicated affair, and that's certainly true here. As you can see, Maekar Targaryen is not the immediate heir to the throne following the death of Baelor, nor is he the next king to rule. But he does climb the line of succession through a series of unfortunate events that eventually puts him on the Iron Throne — just as his son, Aegon V Targaryen, will one day do the same in his wake.
A Knight of the Seven Kingdoms season 1 is streaming now on HBO Max. Season 2 is currently in production.