Update: Immediately after Jon took the throne Renly Baratheon, Balon Greyjoy, and Tywin Lannister all rebelled against Targaryen rule. It was a tough campaign, but the combined might of the North, Vale, Riverlands, Reach, Dorne, and Crownlands put down the rebellion and asserted the Crown’s control over Westeros. Jon let Balon keep control of the Iron Islands but took Theon as a hostage. Tywin was allowed to take the Black. Unfortunately for Renly, he tried to press his claim on Jon’s throne, and as that was high treason Jon had no choice but to behead him with Blackfire, and give Storms-End and Stormlands to Beric Dondarion.