The Leech Lord is a cunning opportunist whose blade has been crucial to the power dynamics in the War of the Five Kings. Bolton sensed the turning tide in the war after the Lannister victory at the Battle of the Blackwater when he ordered his bastard, the vile Ramsay Snow, to sack Winterfell and deflect blame on the turncoat Theon Greyjoy. And it was he who delivered the Lannister’s regards to Robb Stark in his final moments.
Bolton’s objections were rooted in his inability to comprehend how Robb Stark could shatter a politically expedient marriage with House Frey for love, and how Catleyn Stark could release the Kingslayer in exchange for her captive daughters.
Bolton was rewarded for his efforts with stewardship of the North, over which he will rule with sadistic impunity, living up to his house's sigil of the flayed man.
With Walder Frey’s pride wounded by Robb Stark’s broken betrothal, Bolton married a Frey daughter for his own to reap both the political capital and financial capital of "Fat" Walda.
Sharing a mutual disgust for the King of the North, Bolton and Frey plotted the fall of the Young Wolf. At a wedding reception forever memorialized on YouTube, the Freys overran the drunk and unarmed Stark army, slaughtering the Northmen and solidifying the Lannister’s claim to the Iron Throne. For living up to the heights of Machiavellianism, the Washington Free Beacon awards Roose Bolton with a man of the year designation.