A character throughout the whole series, I was never the biggest fan of Charles Brandon. He's good friends with King Henry VIII, so much that he's elevated to being a duke.
But he marries Henry's sister Margaret in secret. Then cheats on her, and she dies. And he carries this dishonorable behavior for most of his life.
While he almost always had the King's favor, when he wasn't trying to ruin the lives of those he hated at court, he was tasked by Henry to do some terrible work. Such as the slaughter of Catholic rebels in the north.
After many years of service (this point is where he starts to look more like the real Charles Brandon) he is estranged from his current wife and lives with a French woman he met at war.
Like Henry, the end of his life wasn't too terribly happy.