|◄ Preceded by||Karl Fritz||Followed by ►|
|Unknown, eventually Fritz||Unknown, eventually Rod and Uri's father|
|◄ Preceded by||Karl Fritz||Followed by ►|
|Unknown, eventually Ymir Fritz||Unknown, eventually Rod and Uri's father|
|Peace was all he wanted. But if Marley grew strong and came to take the Founding Titan or his life, he would accept it. He believed the sins of the Eldians were so grave, they could never be atoned for. 'However, until that day of retribution, let me savor a brief paradise, free of conflict within the walls. That is all I ask of you.'|
|— Karl Fritz's final words to the Tybur family, recounted by Willy Tybur|
Karl Fritz (カール・フリッツ Kāru Furittsu?) was the 145th King of Eldia and the one responsible for its downfall. After the Eldian Empire's collapse, he moved many of the Eldians to Paradis Island where he raised the Walls, and used the power of the Founding Titan to erase the memories of the outside world from humanity inside. Afterward, he changed his family name from Fritz to Reiss and became the first King of the Walls and ruler of humanity inside the Walls.
Karl Fritz was an aged man with long hair and a thick beard.
Karl Fritz' Titan is depicted with long shaggy hair and exceptionally sharp teeth. In contrast to its thick legs, the upper part of its body was quite skeletal, with its ribs visible through the skin. Its arms were thin and long, similar to those of the Beast Titan.
Karl Fritz was a man wracked with the guilt of his ancestors. Even before inheriting the Founding Titan, Karl Fritz detested the atrocities committed by the Eldian Empire throughout history. This intense guilt would lead him to conspire with the Tybur family to weaken Eldia enough for Marley, a nation long oppressed by Eldia, to conquer it and take back their land.
Karl Fritz held the belief that the world would have been better off if Titans and Eldians never existed and he considered his people to be sinners. He believed that if the world decided to exterminate the Eldians, because the Eldians' sins are too heavy to be atoned for, it should be accepted.
Despite this, Karl Fritz and his successors still wish for their people to live in peace and happiness. So he created a "paradise" inside the Walls for them to live in, erasing his people's memories to make them ignorant and blissful, before the nations of the world would inevitably invade. He was fierce at defending the peace inside the Walls and feared the minority bloodlines he could not control; when the Ackermann family refused to be silenced and was immune to the Founding Titan's power, he betrayed them and ordered their extermination.
Over a century before the struggle for Trost District, Karl Fritz was crowned the 145th King of the Fritz family and inherited the power of the Founding Titan. For many hundreds of years, various families subservient to the Fritz family were constantly at war with each other for control over the eight Titans, a civil war which Karl Fritz was ashamed of. Rather than following the method of his ancestors and using the Founding Titan to maintain order in the nation of Eldia, Karl Fritz abandoned the conflict, resulting in the Great Titan War, and conspired with the Tybur family, keepers of the War Hammer Titan, to lead Eldia on a path of destruction. Fritz and the Tyburs fabricated a hero of Marley, a nation long persecuted by Eldia, whose name was Helos. While the world was led to believe Helos continued to instigate the Eldian civil war, Karl Fritz moved the capital of Eldia to Paradis Island to the east of the mainland of their nation. In Karl's absence, the Tybur family gave their support to the oppressed society of Marley, who took part in the Great Titan War in Eldia, gained the power of seven out of the Nine Titans and rose up against their oppressors.
While war raged on the mainland, Karl gathered the royal family and the people of Eldia to the island. On Paradis Island, Karl used the Founding Titan to guide countless Colossal Titans to form three concentric Walls around their territory: Maria, Rose, and Sina, around the last remaining territory of Eldia in which the Subjects of Ymir could finally live in true peace.
When the Walls were completed, Karl gave an ultimatum to the outside world: if any act of war was committed against the remnants of Eldia, the tens of millions of Titans within the Walls would be unleashed upon the world to flatten the entire earth. However, this ultimatum was merely a bluff to ensure lasting peace. In secret, Karl Fritz told his surviving relatives on the mainland as well as the Tybur family that he made a vow renouncing war with the Founding Titan, ensuring that he and his successors would never use its power for retaliation in the event that the Walls would fall under attack. If the day should come when Marley's power was great enough to destroy Eldia, his successors would accept it, though his final wish was to be given an age of peace to enjoy before Eldia's final retribution.
Afterward, with the people of Eldia gathered within the Walls, Karl used the Founding Titan once more to erase the memories of all Subjects of Ymir of the Great Titan War and all of history before the raising of the Walls, as well as all knowledge about the world outside the Walls. However, some Eldian bloodlines who were not Subjects of Ymir were unaffected by this manipulation, such as the Ackermann family and the Oriental clan. To prevent the risk of these unaffected groups spreading information about the world beyond the Walls, Karl offered positions of nobility in Wall Sina to these minority families, and most accepted the offer. However, the Ackermann family and the Oriental clan rejected Karl Fritz' ideology and turned against him. For this reason, Karl Fritz ordered for these families to be hunted down and exterminated.
In order to protect the royal family, Karl Fritz renamed the Fritz royal family to the "Reiss family," who would live in hiding as nobles while a different bloodline would take the Fritz name. To the east of Orvud District, Karl created a massive subterranean cavern where his successors would inherit the power of the Founding Titan. Sometime later, at the end of Karl Fritz's thirteen-year reign, he passed the Founding Titan to his successor. Though Karl had died, his memories and his vow renouncing war would live on in the Kings of the Walls who inherited the Founding Titan after him for the next hundred years.
Throughout the generations, the ideology of Karl was carried through the monarchs of the Reiss family, and none would tell of the history of the Eldian Empire before the raising of the Walls. Karl's beliefs would often manifest outwardly in his successors, such as Uri Reiss's desire for an age of peace before destruction.
Beyond the Walls, the actions of Karl inspired rebellion in Marley. The Restorationists, led by Eren Kruger under the alias "the Owl," sought to take the Founding Titan from the King of the Walls to finally rise up against their oppressors. The Restorationists believed that Karl was cowardly for abandoning his people in the Great Titan War, and by taking the Founding Titan they would restore the Eldian Empire to its former glory. Eventually, the movement was discovered and exiled to Paradis Island, though Restorationist Grisha Jaeger survived to carry out the mission. Inspired by Eren Kruger, who gave him his Attack Titan, Grisha entered into the Walls to begin his search for the Founding Titan.
During the fall of Wall Maria in the year 845, Grisha Jaeger visits the Reiss Chapel where King Reiss's cavern was delved. Confronting Frieda Reiss, he begs for the King of the Walls to stop the attacking Titans for the sake of her people. The vow renouncing war would not allow her to retaliate, and Grisha's pleas are refused. Taking matters into his own hands, Grisha battles Frieda's Founding Titan with his Attack Titan and steals the Founding from her, before slaughtering the rest of the Reiss family except for Rod Reiss, who escapes.
Fleeing the scene, Grisha gives his son Eren Jaeger a Titan injection, passing the Founding Titan and the Attack Titan to him. With no royal blood in him, the Founding Titan becomes unusable and the King's vow renouncing war is not passed on to Eren.
When Eren Jaeger and Historia Reiss are captured and taken to Rod Reiss, he tells the two the history of the Reiss family and the passing of the First King's ideology through the line of monarchs in the past century, preventing the truth of the world from being known to the people of the Walls.
During the Battle of Shiganshina District, Zeke Jaeger laments King Reiss' decision to take the memories of the Eldians away from them after the Great Titan War, leading them to make the same mistakes of the past.
In the aftermath of the battle, the survivors of the Scout Regiment discover the basement of Grisha Jaeger. In the basement, they find three journals describing his life before coming to the Walls. Through his story, the people of the Walls learn of the Restorationists' attempt to take the Founding Titan from the King of the Walls to end his vow renouncing war. With this information, the military of Paradis Island decides to inform the people of the history that King Reiss took from them a hundred years ago.
One month later, following the conclusion of the Marley Mid-East War, Willy Tybur hosts a festival in the Liberio internment zone set to conclude with a play in which he will reveal his plan to solve the Titan crisis. In this play, Lord Tybur reveals to the world that Karl Fritz himself was responsible for the fall of the Eldian Empire. However, Tybur further reveals that despite the age of peace King Fritz wanted between Marley and Eldia, their peace has come under threat due to the theft of the Founding Titan, now held by Eren Jaeger.
Karl Fritz held the power of the Titans, specifically that of the Founding Titan, and displayed many abilities related to that power; some of them at a rather advanced level. His powers included:
- Regeneration: Like all Titans and those with the power of the Titans, Karl Fritz possessed the ability to regenerate any injuries he may suffer, even fatal ones.
- Titan Creation: Karl Fritz turned countless Subjects of Ymir into Colossal Titans.
- Titan Control: He used this power to control the Colossal Titans to build the Walls, by making them harden their bodies and confine themselves into the resulting structures.
- Memory Manipulation: He was capable of manipulating the memories of Subjects of Ymir. Other ethnicities, such as the Ackermanns, the Oriental bloodline, and the noble families, are unaffected.
- Memory Inheriting: He was able to pass down his memories to an unknown member of the Reiss family after dying, making them the inheritor of the lost memories of mankind. This also happened with all of the other inheritors, who inherited the memories of Karl Fritz and the inheritors themselves. However, they and all their subsequent heirs also inherited his belief that a world ruled by Titans would be "true peace." This influence is so strong that even people that wanted to stop the Titans instantly changed their minds when they received the power, deciding not to make a move.