If you open any RPG setting, and most rulebooks, they all seem to include a few pages of lore. For sci-fi games, it might be a potted history of the galaxy. For fantasy games, it'll be a list of the deities players can choose as their patrons, with handy little paragraphs summarising their portfolios and powers.
I'll be honest, I hate it. I get that it helps put some structure around the game, but I feel it makes for shallow settings. It's all too neat and tidy. The real world is riddled with inconsistencies, differing viewpoints, religions torn by schisms.
So in my homebrew world, I've tried to mirror a little of that real-world mess. My players have become used to the idea that the world's history and religious beliefs will wriggle and squirm under them, depending on where they are and who is doing the telling.
What Kinds of Lore Are There ?
In terms of game settings, I think there are three types of lore; that relating to the gods, history lore, and lore relating to people and places.
I'll cover just one of these in this post, but hopefully it'll give you an idea of ways a game can be made to feel more immersive. I'll give examples of the way games tend to present it, how it is in the real world, and how I like to handle it in my homebrew world.
Deities and Religion in Game Lore
In D&D, Pathfinder and most fantasy games (although less commonly in sci-fi games), the gods are given as a list of names, with clear portfolios, alignments, and powers. Occasionally one or two gods may have other gods referred to as their enemies or rivals. But that's it. You have to dig very deep indeed into the source material before you find any kind of "family tree" or detailed information on how the gods interact with each other.
To my mind, it is clear that they are just there to add a bit of fluff for divine character classes to explain where they are getting their spells and abilities from.
How it is in the Real World
In the real world, each culture has it's own god or gods. Where they are polytheistic, there's a mess of contradictory legends about their rivalries, their hierarchy (which often changes depending on where and when you are talking about), and their powers and areas of influence.
In many cases, gods are imports from other cultures; the Romans are a good example, they stole gods from pretty much every culture they came into contact with.
In other cases, they are incremental developments of gods worshipped by previous civilisations. The Classical Greeks took many of the gods worshipped by their Helladic ancestors, dropping some (e.g. Potnia and Smintheus) and changing others (e.g. Potidan who became Poseidon), as well as importing some from Asia Minor and the Near East.
Zeus/Jupiter is actually a bit of a special case, and is one god serving a huge number of cultures. The name is thought to originate from the Sanskrit Dyaus, with D, Z and J being phonetically very similar. That lead to Zeus for the Greeks and Deus in the Latin and Christian worlds. But as the sky god, he was the father, Deus Pater, which was mashed together to make the name Jupiter. When Christianity came along, the old gods became the new devils, and he morphed again into Dispater.
Using Lore To Make A Game Immersive
In game, I try to recreate this kind of complexity in a number of ways. The goal is to add just the right amount of mystery and uncertainty. I feel it is also useful for players to understand that where deities from "the rulebook" are used, there will be more involved than just the words in the book, and that deities pulled across from real world myths may not be 100% familiar and predictable.
In my homebrew world, there are two or three main "pantheons" (shamelessly stolen from "real world" mythology and D&D lore) plus a number of individual deities. But the forms of worship and how people represent their gods vary wildly from place to place. To a barbarian tribe, Odin is a shaggy bear-god worshipped with blood sacrifice and drunken revels, while to a civilised medieval-style culture, he is a valiant warrior god modelled after an idealised ancestor and worshipped with formal ceremonies and prayer.
I've also made a few subtle changes to the gods' portfolios, both in terms of content and varying them geographically. Not enough to make the gods unrecognisable, but just enough that players can't feel like they know all there is to know about them. Thus a goddess of love in one area is seen as a goddess of dark lust in another. There's a part of the world where I've used Celtic deities, and it's become a bit of an in-joke with my players that all of them are a god of something "and war".
One important thing is to never give gods a stat block. Players joke that anything with stats can be killed, which kind of takes away a lot of the mystery. It's my personal belief that gods should be so far above mortals that killing or banishing them should be a complete story arc only for the highest level players and only with the help of special divine assistance and (loaned !) weapons.
Something I never do is bring into the game any deities from real-world monotheistic religions. Far too risky ! Polytheistic religions tend to be quite tolerant of other belief systems, but monotheistic ones by their very definition tend not to accept the existence of other deities. I prefer to keep my conflicts strictly in-game, and to avoid doing anything which might offend my players.
Finally, I don't worry too much about long-term consistency. The homebrew world I run has been going for about 40 years, changing and evolving through that time. Every party that adventures in it makes new legends, and it's impossible to remember everything that has happened. If a player queries an element of the lore, I just take the view that they heard it from an NPC who didn't know the whole truth. It's rarely significant enough to have a serious impact on gameplay.
So how do you feel about this ? Do you like your lore simple and uncomplicated, so that players know where they stand, or do you prefer it to grow organically and risk confusion ?