Mitras

Mittorasu-Ōto (ミットラス王都) is the area of land surrounded by Wall Sheena, the innermost of the three Walls, and the capital of the nation of the Walls. It is the residence of the King and upper-class citizenry.

The Female Titan arc
After the failure of the 57th expedition, Eren Yeager is supposed be returned to the Inner District for judgment. However, he never arrives. The true purpose of the trip is to expose the true identity of the Female Titan, Annie Leonhart and she is revealed in Stohess. After being discovered, Annie attempts to scale the Wall, but she is stopped by Eren in his Titan form with the aid of Mikasa Ackerman. Part of the Wall suffers damage and reveals a Titan within it, but is quickly covered up at Nick's urging.

The Uprising arc
Erwin Smith visits the capital in response to a summons by the chancellery. As he rides in a carriage with Nile Dok, he is surprised to see that child thieves are common now, even in Mitras. His meeting goes poorly as he discovers the government officials are more interested in protecting their authority than the rest of humanity.

After Erwin is arrested for the alleged murders committed by the Survey Corps, he is brought to Mitras for his audience with the king. Public gallows are erected in expectation of his execution. Nile tells Erwin that he expects Erwin to be dealt with at the same time the Survey Corps is disbanded.

Erwin defends the necessity of the Survey Corps to the king and the other high ranking members of the Royal Government, but his words fall on deaf ears. Seeing that they are unmoved, he asks if they have a secret plan as an alternative. The officials redirect the subject to the deaths of several members of the Military Police Brigade at the hands of Levi and advocate his actions as a threat to the peace. There is no need to tolerate such a group within the Walls. They then give the order for Erwin to be taken to the gallows.

Before that can happen, Anka Rheinberger bursts in announcing the fall of Wall Rose and that refugees are fleeing towards Wall Sheena. Dot Pixis immediately calls for his soldiers to secure an evacuation route, making it a top priority. However one of the officials countermands his order and commands that Wall Sheena be shut to all refugees. Nile protests that doing so will sacrifice half of humanity, but the officials do not care because that number of refugees might be enough to spark a civil war.

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