Yeah so the emperor had the Sardaukar, his elite military force, as well as a bunch of conventional forces. The Sardaukar as well as most of the Harkonnen forces are the ones who ambush the Atreides in the first part.
So that's the big shock for Paul and Leto, that the Emperor did hire his forces out to the Harkonnen. That's a huge deal, a step they considered beyond the Pale; the Emperor never hires out his Sardaukar, they're his trump card. It shows how concerned the Emperor was about the chances of House Atreides standing against him.
Who was the emperor affiliated with? Did he have his own armies?
Yeah so the emperor had the Sardaukar, his elite military force, as well as a bunch of conventional forces. The Sardaukar as well as most of the Harkonnen forces are the ones who ambush the Atreides in the first part.
Oh, I thought the sardaukar were mercenaries, but idk, the emper can hire out his forces as a treat.
So that's the big shock for Paul and Leto, that the Emperor did hire his forces out to the Harkonnen. That's a huge deal, a step they considered beyond the Pale; the Emperor never hires out his Sardaukar, they're his trump card. It shows how concerned the Emperor was about the chances of House Atreides standing against him.
I'm not sure how much this was transmitted in the movie, but now I've spent a while reading wiki entries