I love Glorantha. Its a rich world with its own interesting cosmology and a wealth of myths. I would love to run a campaign in there. Just to get really into all the stuff I love. And I never should. Sure, I’ve tried, but it just doesn’t seem to work out. Why? Because I can’t ever communicate all things I want to any potential players.
So, maybe the answer is having them read plenty of background material. Feels like a mistake to me.
First, you’re supposed to have fun and people don’t want to have extra chores attached to their fun. Not everyone has time to read what you give them, or they just forget. Its not like their going to set aside time in their calendars for it.
But that’s not the actual problem. The problem is, as much as you think what’s obvious on the page, just isn’t. People approach text from different perspectives and especially when you talk about established genres, they have different reference points. They take what they think is important and go with that. They might miss details that you think are very important, maybe even crucial, but since they can’t know what’s important beforehand, they’ll try to find what’s important, but they will always understand that differently from you, because they are different.
Its very hard for you to know what they want get. Trying to be coy will just end up with your “cleverly” designed details being totally ignored. If you tell them or just hint that there’s some important detail they’ve missed in the background material, what will happen is that your players will find quite a few details, most of which are meaningless.
I’m not saying you can’t tell players about the world, but you have to find common reference points and you have to make it short. When I try explain Glorantha, I get nowhere. If I tell players, who have played King of Dragon Pass, that its that same place, but a few hundred years later, when the clans, tribes and kingdoms are much more cemented, than they will get what’s going on.
Of course, if you are doing something completely original (you probably aren’t really, but different enough to be outside of most people’s radars), you have to explain it somehow, but even then it can be an amalgamation of different sources like the school from Harry Potter running a Jurassic Park in ancient Mesopotamia (no, I didn’t think that through beforehand, but if this happens to be exactly what you are looking for, then welcome).
Just don’t make them watch all eight Harry Potter movies, all four Jurassic Park movies and all possible versions of 300.