actors resemble their real life counterparts
Surprised no one has mentioned this already--
What REALLY struck me about this series is what great pains the actors took to LOOK their parts!
Henry VIII obviously goes without mention. (His metamorphosis from young man to corpulent tyrant was INCREDIBLE!) Then there's Katherine of Aragon, who is FINALLY portrayed as having reddish hair, just like the real Katherine. Anne of Cleves looked JUST like her infamous portrait. All of the other wives were spot on as well. Simply amazing!