Worldbuilding is at the heart of the gamesmaster (GM) process — your players’ characters need somewhere to exist. Eventually a player is going to ask what is over the hill, or beyond the horizon; and you need to be able to give them an answer, or at least an adventure that leads to an answer.
There are many different published settings out there and you might think that using one of these, or perhaps basing your game on the setting from an established franchise from other media, might get you off the hook. These can be a great starting point, but I’m afraid you will still have some work to do. These settings can give your players a common starting point for beginning to understand how the world works, and it can certainly let you put off some of this work until you’ve started the game and can get a feel for the dynamic. However, the time will come when you’ll be asked a question that the setting — or the TV show, film, book, or whatever — doesn’t readily provide an answer for, or you might need to change something because it doesn’t quite fit what you need. Perhaps you want to just make changes to keep players that know the setting well on their toes. For whatever reason, you can’t entirely rely on these published solutions.
Worldbuilding is an art which can be done in several ways and all GMs will find their own style, or even different styles depending on the need of the individual game. I tend to think of these styles as being points on a 3D graph, with the three axes describing different extremes — more on this shortly. I’m going to assume that the gamesmaster will be primarily responsible for the worldbuilding, but that isn’t always the case — 13th Age, for example, encourages the players to get involved, and Dresden Files has players creating their city collaboratively as part of character creation.
The first of these three axes is preparation versus improvisation. If you want to prepare your setting in advance you are, of course, talking about a lot of work before the game starts, either in terms of design work or reading up on the material you intend to use. You probably need to do this before you even invite character concepts, as many players will want to tie their character to the world in some way. The great benefit is that you should end up with a very consistent world, and you’ll be ready to answer those questions that players raise with a minimum of effort. You might have to change things as you go along, but you’ve frontloaded the work — so the session-to-session work, and the actual running of the game, should be much simpler.
Improvisation, on the other hand, allows you to much more easily react to what the players do and the needs of the story. I’d strongly recommend making careful notes as you go along, should you pursue this option, because answers to ‘what is beyond the forest’ changing each session will spoil player immersion. Another danger is poorly-done improvisation — struggling for a name and then using a joke one might be funny at the time, but these are often the characters that players latch onto and you might regret it in a few sessions’ time.
Tacking to either of these extremes will probably lead you to problems and may well be impossible. You need some idea of the world for your players to fit their characters into it; and, equally, you’ll never manage to answer every question beforehand. Where you want to land on the scale will be a matter of personal preference and confidence. Even if you are using the real world as your setting, you’ll need to change something or add elements; and even if you want to completely improvise I would strongly recommend at least having a list of names handy.
The second axis refers to your starting point. I call one end ‘top-down’, and the other ‘inside-out’. In top-down worldbuilding you start with the big picture — be that the galaxy, the planet, the dimension, the country, or whatever else — and start to map it out. This doesn’t necessarily need to be detailed (for example, you don’t need to know the name of the king on the other side of the world), but you know what the world looks like and where things are. You can then, once you have a big picture, start to fill it in.
Inside-out worldbuilding starts with a small location — a village, say, or even a first dungeon — and you only start to worry about outside of that small environment as and when it’s needed. That doesn’t mean that the world is entirely improvised — you can ask your players what their intentions are for the next session, giving you some time to prepare the next area.
Which of these you want to use will probably depend mostly on the scope of the game you’re planning. If you are looking at a small party of heroes who go from town to town solving problems, inside-out is probably your best bet. You only create the world as and when it’s required, and you don’t need to worry about larger issues or politics unless it actually impacts on the game. On the other hand, if you intend that your player characters will eventually get involved with issues on a country or world-wide scale, then the top-down view will probably help you more — you’ll have a better idea of how each nation impacts on the others, and the politics should flow naturally from that.
Note that these techniques can work whatever scale you are working with, and whatever genre you are using for your game — you just need to keep in mind travel times. Your starting village in a Dungeons & Dragons campaign might be a starting planet in Star Trek or a neighbourhood in a superhero-style game. Your fantasy region might be a solar system in a science fiction setting, or a city for a game revolving around superheroes.
So far all of my examples have been geographically-based — asking questions about villages, countries, and so on. However, the third axis turns this on its head. Geographical is one end of this axis — the other is temporal. In some games, the history of the world may be just as important as the geography and, for example, the historic reasons for a war between two cultures might lead to a solution to that conflict in the timeframe of your game. If you are dealing with prophecy, you might need to think about both the history and the future; this is equally the case if you are considering how technology levels may progress in a science fiction setting.
At the geographical end of the axis, you create your world and then you work out reasons why it is the way it is. You might fully prepare your map and answer historic questions through improvisation. The other end of the axis starts with a timeline, and then works out what kind of society and geography those events might have led to — again, either or both might be prepared or improvised. The issue here is: which do you think about first? Which is the cause, and which is the effect?
If you are working with a history, rather than a geography, you still need to make a decision about where to be on the top-down/inside-out axis. In this case, top-down looks at a big picture timeline with big events filled in, and then you look at the detail (perhaps your history can be split into ages, or occasional cataclysms). Inside-out looks at a particular point on the timeline (typically the present) and works outwards, working out causes of events in reverse.
I’ll give you a couple of personal examples to illustrate. The game I’m currently running uses the 13th Age system, and I’m using the Dragon Empire (the default setting) largely unaltered (though it is not particularly detailed — it expects player participation in worldbuilding). All of my players chose to create elf characters, which meant that I could start by focusing on that particular culture and part of society before widening out. History has been important, but long enough ago that it could be referred to vaguely for the most part; only recently have I filled in a top-down timeline.
Alternatively, in a previous game, all of the characters had amnesia and woke up together in a dungeon. In this case, I created my own world so that my players would know absolutely nothing about it before we started — and a great deal of that world was improvised as I went (though I had created a rough map and had written a pantheon of gods). However, I wrote a small flashback vision for each character each session for them to discover their backstories and how their personal history related to the plot, and as a result my history of the world was very detailed from the start.
The key lesson here is that almost any point on the model (with an exception for some of the greatest extremes) can work. Most GMs are going to be somewhere in the middle, depending on their own preferences, experiences, and confidence. Each has its own benefits, and, with care, you can balance them out and take advantage of all of them.
Personally, I tend towards the improvisational and inside-out (I’ve had far too many games where my preparation has been wasted because the players went a different way). However, one of the best games I ever played in was extensively mapped-out — to the point that the characters found a copy of the map in the early sessions and relied on it extensively!
No matter your style, worldbuilding comes down to asking questions; and, hopefully, asking them of yourself before your players do. Why are these two countries at war? How come this landlocked town has a port? Why is this village called Riverside even though there isn’t a river for miles? From where does this city get its food? Who colonised this planet, and why did they do so?
From these initial answers, more questions will be raised. Not all of them will be relevant to your story, but every question you answer adds a little detail to the world that might inform something else. This is the greatest strength of preparedness — you give yourself time to answer those questions, consider the implications, and fall down the rabbit hole. The same process applies if you are improvising, but you’ve given yourself less time to consider the natural consequences.
An important aspect to keep in mind is that these are largely the same questions no matter what setting or genre you are working in. People are still people, and all of the reasons a setting is the way it is come down to decisions that people (albeit fictional ones) have made. Even if you’re trying to use a setting where the people are very alien and difficult to understand, you are still asking yourself how they are different. Your biggest tool is ‘why’ — very closely followed by the other questions.
Naturally, not all games will need this level of consideration — sometimes you just need a dungeon and a vague reason to be in it. However, putting some thought into these questions can help bring some authenticity to the world you are playing in, and to the game. And authenticity is what you are aiming for — not necessarily realistic (realism is a different thing, of course), but something that makes sense internally.
Remember, though, that you don’t need to do this too much — at least to start. If that empty map is too intimidating, just pick up a setting book or create your starting village — you can always build from there. In time, you’ll want to start putting your own stamp on a world.