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In page Anna of Hungary, Duchess of Macsó:

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Stephen was infuriated and immediately revolted against his father; during the ensuing war, Anna and her son, Béla of Macsó assisted Béla IV.[1] Anna's father and brother concluded a peace on 5 December 1262, and according to the peace the kingdom was divided, the latter acquiring the territories east of the river Danube as “junior king”. After the peace, Stephen V occupied the possessions which Anna's sons had inherited from their father in the eastern parts of the kingdom (the former royal possessions in Bereg County and the Castle of Füzér). Anna submitted a formal complaint against her brother to Pope Urban IV, but the "junior king" did not hand back their possessions.[citation needed]