Yeagerists

The Yeagerists (Yēgā-ha) surface in 854 as a clandestine faction of soldiers and civilians assembled by Floch Forster in service of Eren Yeager's designs. Their opening objective is to reunite Eren with his half-brother Zeke and clear the path to the Rumbling; within a month of the raid on Liberio they stage a military coup, and days after the Rumbling begins they hold uncontested power over Paradis. By 857 the movement absorbs the three old military branches into a single force, the Eldian Army, devoted to defending Eldia against whatever survives of the outside world.

Ideology binds the faction together. Its followers hold that Eldia stands at the brink of annihilation and that only total devotion to Eren can avert it, dismissing the Royal Government as a relic waiting to be swept away by foreign powers. Xenophobia runs through the movement, hardened by generations of Marleyan aggression and the world's branding of the islanders as devils, and its most radical adherents revive the supremacist thinking of the old Eldian Empire, dreaming of a New Eldian Empire with Eren enthroned through the Founding Titan. Grisha Yeager's journals, which taught the islanders the truth of their history, feed the same fervor.

For all its fanaticism the faction is coldly pragmatic, cooperating with Yelena and Zeke's volunteers while their aims align, tolerating openly hateful partners like the Marleyan Griez, and offering the Anti-Marleyan Volunteers a future as honorary Eldians even while copying Marley's own methods of subjugation, down to sorting suspect soldiers with colored armbands according to who drank the tainted wine. The takeover unfolds in stages: sympathizers distribute wine laced with Zeke's spinal fluid to the military's senior officers, a chair bomb kills Commander-in-Chief Darius Zackly, and Eren tunnels out of prison with the War Hammer Titan's power while his followers free his allies. Rejecting Dot Pixis's offer to negotiate over Zeke's location, the Yeagerists seize Hange Zoë to extract it, win over the 109th Training Corps after having sympathetic trainees beat their old instructor Keith Shadis, and soon control effectively everything inside the Walls, fielding around 500 soldiers in Shiganshina when Marley's surprise attack arrives. During that battle the Marleyan Warriors Pieck Finger and Porco Galliard expose themselves as infiltrators within Yeagerist ranks, and Floch's ambush squad is wiped out around the Cart Titan's carcass, leaving him the sole survivor.

The Rumbling splits their fortunes. Crowds hail Eren as a liberator, writing off the Eldians crushed beneath the falling Walls as noble sacrifices, while the leadership hunts his former comrades. Floch orders the execution of Yelena and Onyankopon, occupies the island's harbor to keep the makeshift alliance from Kiyomi Azumabito's flying boat, and is routed when the Armored and Female Titans enter the fight; shot by Gabi Braun and clinging to the fleeing ship, he reaches Odiha and fires on the flying boat before dying, begging his old comrades with his last breath not to stop Eren.

Eren Yeager stands as the movement's symbol and Floch Forster as its operational leader; neither lives to see its final form. Rico Brzenska and Hitch Dreyse number among the soldiers folded into its ranks, and Louise, Wim, and Holger are early sympathizers arrested for leaking word of Eren's imprisonment. Samuel, Daz, and Oliver die in the faction's service. After Eren's death costs the world eighty percent of its population, the surviving Yeagerists pour their energy into militarizing Eldia against retaliation, rallying behind a slogan that urges Eldians to fight because victory means life and defeat means death.