I recently did a little quiz on my players. I asked them basic questions about the Dark Heresy universe, such as: what is the Angevin Crusade?
who was Saint Drusus?
what can you tell me about the planet called Dusk?
what is the Chaliced Commissariat?
who are the Pilgrims of Hayte?
what is the Mara Landing Massacre?
what is the capital of Scintilla?
.. and found that they didn't know a lot. Some did. But most were pretty ignorant about the setting and its main themes and background fluff. Most did not even know that Komus is the Tyrant Star!
Now don't assume my players are dumb and uninterested. They are not. But being the GM, I have all the books and spend quite a lot of time reading them, preparing adventures, and linking background fluff (just look at the Haarlock thread
. Most players have the core rulebook and maybe the Inquisitor's Handbook, and that's it. I can't blame them for not knowing more than they do, yet I wish they did, cause I feel the enjoyment of the game would be greater if they knew rightaway the terror of Dusk when that planet is being mentioned ingame, if they could quote Sebastian Thor, and picked up clues about Komus.
Familiar problem?
any suggestions how to remedy this?

Most every game I run I require players to fill out something along those lines, especially if they are having problems with concept.