Catherine of Aragon at the Legatine Court. It's a triumph not only for Catherine, but for Maria Doyle Kennedy who played her. And in that moment, when she walks out of Blackfriars with her head held high and the people begin to cheer, everyone knows that no matter what comes, she will always be England's true queen.
Extra points for being a CMOA in history too; the speech was cut down and translated into modern English, but was essentially the same thing said by the real Catherine at the Blackfriars trial.
Anne Seymour in the last episode, when she calmly informs the feared bishop Gardiner that he will not serve that warrant and why.
Katherine Parr, also in the last episode when she manages to convince Henry that her religious debates with him were meant only to distract him from his painful leg ulcer, thereby saving her own skin—which no previous wife managed outside of Anne (see Extreme Doormat). Again, extra points for being Truth in Television.
Anne Stanhope blackmailing Bishop Gardiner, Katherine Parr convincing Henry not to kill her over her religion, and Edward Seymour decking Bishop Gardiner in the series finale.
Also in the finale, Henry is haunted by the ghosts of his first three Queens, none of whom are particularly comforting to him. Extra points for Jane accusing him of pushing their son to an early death, since of all three, Jane would be expected to be on Henry's side.
Anne Boleyn's execution in season 2, when she faces her death with such dignity and poise despite earlier breakdowns
Earlier, Thomas More's own execution is the epitome of Face Death with Dignity. Hell, everything about that man was dignified... except for his tendency to brutally burn people for heresy.
After tiring of Bishop Gardiner's constant investigation and burning of protestants. Henry gives a passionate speech about how he is fed up of it to one of his aides. When Gardiner requests a audience, the aide sums up the speech simply as 'The king requires you to leave court'. Gardnier's face goes white and borderline flees the palace.
Surrey, Suffolk, and a handful of English soldiers cutting down a party of French skirmishers during the Siege of Boulogne.