In Season 6 of Game of Thrones we see Ramsay Bolton murder his father, Roose. Then the Karstarks and the Umbers declare their support for Ramsay. Reasons why I find this hard to believe:
- Ramsay is a psychotic sadist but not shown as particularly competent at ruling or war. More importantly (given the setting) he's a legitimized bastard. His highborn father and newborn baby brother (both of whom he kills) should command far more respect. How did the Karstarks or the Umbers not try to arrest him or seize his titles?
- Roose is a sociopath too, but also a proven military leader and ruler who has managed to come out on top in the most destructive conflict in 15 years. The Karstarks were already pledged to him; what prompted them to throw in with Ramsay after he killed the guy who actually knew what he was doing?