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The Eldia Restorationists (エルディア復権派 Erudia Fukken-ha?), also known as the Eldia Revivalists or Eldia Secessionists were a rebellious group of Eldians in Marley with the goal to receive the power of the Founding Titan in order to destroy Marley. In contrast to the teachings in Marley, they believed in Ymir Fritz as a goddess who brought cultivated lands, built roads, and brought wealth to mankind. The symbol of the group was a cross-shaped scar on each member's body, which they make themselves with a knife. They received high-profile information from "The Owl", who was an informant in the Marley government. Many of the documents contained an unknown writing.
The remnants of the royal family that stayed in Marley formed a revolutionary army, however, this army was unsuccessful in bringing about any change. All members of this original organization, including Eren Kruger's father, were smoked out by Public Security Authorities and executed for treason against Marley.
Grisha Yeager joined a new incarnation of the group at the age of 18 when a member of the organization came to his clinic and told him that they received information that his sister had been killed by a man in the Marley authorities. There, Grisha devoted himself to interpreting ancient text and planning to revive Eldia. In this organization, he also met his wife, Dina Fritz, a woman of royal blood whose ancestors decided not to move to Paradis island. She gave birth to their son Zeke Yeager. Grisha was sure he would lead them to victory over Marley. When the Warrior program of the Marley government was proclaimed, he planned to make Zeke a warrior who was then supposed to turn against Marley. However, at the age of 7, Zeke reported his parents to the authorities of Marley and the Eldia Restorationists were arrested, to be sent to Paradis, where they would roam as mindless Titans for the rest of eternity.
Before being sent to Paradis, Grisha was tortured by the authorities for information such as the Restorationists plans, and the identity of "The Owl". After this, the organization members were shipped to Paradis in preparation of their execution. All members of the group were transformed into mindless Titans, except Grisha, who was kept alive by Kruger, apparently for further questioning. Once most of the public service authorities had returned to their ship, Kruger saved Grisha from execution by killing the final authority left on the wall. He then revealed himself as "The Owl", transformed into a Titan, and begun slaughtering the other authorities.
After returning to Grisha from his massacre, Kruger explained his reasoning for saving Grisha and gave him a mission to restore Eldia's freedom and dignity by entering the Walls to retake the Founding Titan. He explained that Grisha would do this by using the Titan powers he would give to him. At first, Kruger was met with resistance from a burnt out Grisha, but after giving him a picture of his family and delivering a powerful speech, Grisha's will was reignited and the mission was accepted.