Building Your Own Campaign Setting and its Benefits
The Benefits of a Shared World
I have been playing D&D with the same group for over 14 years now, since I was 11 years old. Every single time it’s my turn to DM for the group, I always run the game in the same exact world, usually at a different time frame than a previous campaign. The result is a world that has had time to evolve and mature, like fine wine or a dry aged steak, where the players know the general mannerisms of different cultures, they know the pantheon, they know how travel works from place-to-place, they know about the histories of the world, they know the origins of various mysteries. Most importantly, to me and to them, is that their accomplishments are recognized and their actions echo throughout history. It’s the same world, which means it’s the same world where they stopped an abomination from assimilating the entire world into its body mass, and there are still NPCs and history books which reference that calamity. It’s the same world, so when the kingdom in which the significant majority of gnomes in the world was besieged by an army supported by the party was wiped out, gnomes became an endangered species and players now need approval to even play a gnome. It’s the same world in which the players encountered a homebrewed trap with a homebrewed alchemic item that now is sold on shelves in alchemist shops throughout the land. It makes the world feel lived-in and real when all of the small details add up over time, and it’s something truly beautiful like a platonic love letter from you to your players and back.
Leave Room to Grow
Not every homebrewed campaign setting needs to cook for a decade to feel good. It’s important to realize that imperfections are natural and to be expected. There should be gaps in the world building, and you’ll realize this when your player asks a question you never thought of, and at that point you get the blessing of collaborative story-telling: wait for your players to tell you what they think it is. When they do, you can either tell them you’ll get back to them (because you’re going to cook up a real answer late) or tell them they’re actually correct and simply subsume their idea into the greater canon of the world.
Start With a Vibe
But where to start? There’s so much that goes into world-building, and there’s not one true answer for everyone, but for me the clear choice is to start with a vibe. The vibe of a world is rather vague, and intentionally so, because I find that a campaign setting works best when it’s not one-note. What that means in the end is that your “vibe” should be much more like a subgenre than a specific idea, i.e. medieval high fantasy or Lovecraftian Babylon as opposed to a military campaign or political espionage. The reason behind that form of vibe selection is that it opens the door to future campaign opportunities and even if you only want to run one campaign with the setting, it still provides room to breathe if and when the scope of an adventure gets out of hand, which is likely.
Build a Map
Once you’ve picked out a vibe, it’s time to get a map together. Yes, this early. When I was a dumb 12 year old, I had absolutely no idea what I was doing, but I did know what I wanted the world to look like… kinda. So how do you get a map? Well, what I did and frankly recommend is to just find a map generator online that you like and literally spam out as many maps as you want until one just looks “right” to you. I especially recommend looking at geographic features and extrapolating what you think goes in unique locations. For example, when I generated the map I ended up using to this day, I noticed that there was an absolutely MASSIVE mountain range, and instantly knew that the dwarven capital of the world had to be somewhere within, and a particularly dense forest led me to imagine what a society would look like if they lived above ground but couldn’t see the sun through the foliage. Another option is the tangerine trick where you peel a tangerine, trying to keep it all in one piece, and then lay out the peel on a table and rearrange the peel(s) until it looks right to you, and then draw it. Lastly, there's the option of literally randomly scribbling on a piece of paper more or less randomly until something looks right to you. The key for this step, which is even more vague than the vibe, is that it has to “feel” right.
Choose Important Locations
Now that you have the vibe and the map, it’s time to pick out some locations to be important. I recommend looking at the map to find cool looking (or sounding if you used a map generator) spot and let your mind run wild. For me, the massive mountain range I noticed on the map was called The Spires, which immediately sent me to imagining a smattering of mountains which seem almost unnaturally thin at their various peaks, like some massive creature splintered the mountainside. To the East of the Spires are the Obsidian Wastes, a desert biome. Why would it be named anything to do with obsidian if it’s a huge desert? My conclusion was volcanic activity on The Spires left obsidian on the exterior of the spindly rock formations that gave The Spires its name, then one day a violent eruption sent that obsidian careening over the wastes, depositing massive chunks of obsidian. Some of which remains to this day and some of which has eroded down with the winds and sands, leaving a blackened hue to the shifting wastes. That’s the mindset you should be in when giving flavor to the locations on the map: just look at it and ask “why”. Why does it look like that? Why is it called that? Why is it next to this other thing?
Populate Your World
Locations can, in most cases, be further enhanced when you start to actually determine who, or what, lives there. Let me stay with the existing context, here: the Obsidian Wastes… who would even live in a desert of their own free will, let alone a land-locked desert, so miserable to inhabit it’s called a waste. I decided on a tiny, insignificant village clinging to the prospect of the well that was dug as leaving would’ve been too costly and risked too many lives. That village grew over time, eventually becoming a small city with massive sandstone walls to protect them and the traders who helped them grow the community from marauders. I wanted a place like that to have a benevolent leader. A king who, despite his royal status, was a salt of the earth man who would fight and die for each and every citizen of his, a man who defended the rights of those citizens to exist as they pleased. Then I asked the question, “Why is he so benevolent?” It was a tough question, at first, but after deliberating I decided he was the son of a particularly cruel and greedy king. Much like with real-life history, which I recommend leaning on for inspiration, the king detested the state of his modest kingdom and its people: destitute, starving, at each other's throats, and only one man to blame. The modern king deposed his father to usurp the throne and lead his people to greatness. In the end, I had a city with a king so focused on keeping his people safe and happy that worshippers of gods of completely opposite alignments or domains could sit at the same bar in peace. That’s the location that I started my first campaign in, and it’s one that’s grown so much over time, evolving as the players have interacted with the people and politics at hand. Today that insignificant village is a fully-fledged empire, having expanded to inhabit most of the wastes, providing food, water, and safety to all of its citizens. Its massive sandstone walls from all those years ago are dwarfed by the concentric rings of the city, like a desert version of Ba Sing Se. To digress, adding flavor to the worldbuilding of locations is much like the South Park style of writing, which is, “This happened, and therefore this happened. Therefore…” Rinse and repeat until you’re satisfied and then pick another spot on the map. Do this at least 3-5 times, and you’ll have some major locations fleshed out, some things you can mention to your players to make your world feel lived in.
Use History as Inspiration
Like I said, use history to inform the world as though it were a real place from history. If you’re placing a city on a coast, it’s likely that they’re some kind of trade hub like Venice, so what do they trade? If a location has a narrow pass between mountains, maybe the people who live there have a stronghold that defends a kingdom to the South from barbarians from the North, or even just enforces a toll due to holding the only land route through the passage. Super tall mountains next to flatlands could imply a society which relies on flight or even teleportation to be accessed, like a mage’s academy seeking solitude or a community of winged creatures avoiding attacks from land-bound creatures (think the reasons why a monastery would be up on a mountain). If you’re looking to populate a set of islands in the middle of the ocean, what does their economy look like? Do they rely on fish, because the earth is impossible to fertilize like the natives of the Pacific Northwest? Do they pillage passing ships as pirates because they’re bloodthirsty and need to make a living somehow? Maybe they raid the other coasts like the vikings did? So on and so forth, adjusting as necessary until you’re satisfied that the societies you’re creating feel just right.
Save Deep Lore for Later
Maybe this feels mundane, or straight-forward, what about the magic system and gods and beings higher than gods and the origin of the universe itself? Well, those are questions which, while interesting, the average player might literally never even once ask themselves or you. Not that you shouldn’t think about them or flesh them out, I mean I have. What I’m saying is that these are items that don’t need your immediate attention, and that I think can often be best left for later, especially when you use collaborative storytelling from your campaign(s) to inform those decisions. If you want to decide on a pantheon of gods, go for it. If you want to give them names and domains, and general alignments, great! But when it comes to determining the finer details of things like these that are far from the player, I recommend just leaving it when you’re first starting out. For me, I didn’t decide on the origins of the universe the campaign setting takes place in for about ten years, and it’s never once been asked about. I decided on a general pantheon of gods, which was fairly easy as most of the gods had already been killed in my setting due to the events prior to my very first campaign (the antagonist was responsible). I decided on the origins of magic and how magic really works only last year, and again, no one has ever asked me about it. I love the flavor overload that I get when I think about it, but unless a given campaign or quest or history book is going to dump that information to a player, you don’t really need to answer these things, even if you’re gonna use this setting for decades to come. If you’re putting the players on a quest for a certain god, then yeah, maybe flesh out what their worship looks like, what level of devotion their worshippers have, maybe what their divine sigil looks like, or even what they look like if the players will actually meet them. Otherwise, these are things that can remain obscure until you get a really good idea that you want to canonise on the fly or your player asks a question that needs an answer. Honestly, even when your players ask you those questions, it can sometimes be even cooler to go, “No one knows” and leave it a mystery.
Start Telling Stories
After all is said and done, what you should have is a world that you can work with, as a DM and as a player. A world which has enough history to answer a question, and enough mystery to make people want to ask those questions in the first place. We have a tapestry upon which to tell our stories, so all that’s left to do is decide what stories to tell. See the handbooks on Session 0 and Running Campaigns to help get started with this.