One of my favourite things about his dark materials is how well it creates cultures and expands upon them.
Each group of people we meet is unique, with their own traditions and taboos.
You never touch another person's Dæmon.
Scholastic Sanctuary, the fear of Dust, and the contrast between Lyra and the scholars in Jordan college.
The nomadic practices and songs of the gyptians, who I was legitimately surprised about when I learned that they weren't a real but niche culture.
Bears do not kill other bears, but also do not pick on the weak. Iorek accepts his exile with humility. He knows what he did. Plus the idea of making armour with meteorites, which are commonly found at the poles due to both magnetism and the fact that they are easily spotted in the snow.
The Magisterium, who legitimately believe they are enacting the word of god.
The north, Lyra's world's equivalent of the wild west, with balloons instead of horses.
Cittagaze, the honour of the knife, how the children have accepted their fate and try to enjoy the time they have left.
The witches, one of the most interesting interpretations of witches and druids I've seen. Not generic 'ooh wave the wand and cast magic' but instead powers far more unique and tied to the world. Separation, flight from CLOUD pines, and making yourself boring.
The Mulefa. Pullman made motorcycle gazelles and made them legitimately believable as a species.
The angels. Not a unified force, but one twisted just like the Magisterium by doctrine and lies.
Edit 2: and now Gryphons and their Gold.
I love HDM.
Edit: removed a section on Book of Dust as I have mixed feelings about it and I don't think it's relevant.
