This is a question mainly directed at people who run homebrews- in developing mine, I always have the question in my head of "how big should this region be?" I sort of have an idea of whether I want it to be a city-state, small country, intermediate country, or a vast kingdom/empire, but the actual measurement in miles sometimes get to me. I want there to be enough room for all the adventuring I could possibly dream of putting in the region, but I don't want to make it so huge that it seems impractical, or each country so large that it would be almost unheard of for a traveling merchant or such to cross several kingdoms.
Right now, I have the idea that a city-state's territory should cover anything from a 100-mile diameter or less, while a small country should by 101-200 miles across in its largest direction, an intermediate being 201-400 miles across, and vast kingdoms/empires covering everything above that, with an average ranging from 500 to 700 miles across.
But, then sometimes I get into the mindset that, "You know, it doesn't really need to be that far apart. Travel times of 5 or more days aren't necessary for every adventure. In a standard D&D setting, which Saern pretty much is, 50 miles or so is probably a pretty good distance to place things apart from each other."
So, I'll go into a phase of designing things on a very small scale, only to come back and feel that it's all too crowded and needs to be redone, only larger and more spread out this time.
And it's not just city placement and political boundaries, but also, and mainly, geographical design. In the main country of my setting, Merithil, there is a lot of detail, but sometimes I wonder if it's too much. The country is about 600+ miles wide, borders the sea on the north, and has four mountain ranges (two of which are only about 30 miles wide and maybe 150 long), two large swamps (one infested with demons and their cultist, the other created by a necromancer lich and covered with undead and supernatural cold), an elven kingdom, a dwarven kingdom/temperate desert, two inland seas (one of which is only about 30 miles by 100 miles, the other much larger), three regions dominated by vast roling plains, two large elven forests, two areas of rugged hills... and I think that about covers it. Is that too crowded? Should it be more along the lines of, oh, maybe 1,000 miles wide, rather than its current 600 by 300?
How long/wide should a typical mountain range be? That's a key one for me, as I really love using them for border separations... possibly too much. I keep trying to design the world where there are many features put together, so that if I want an adventure set someone of vastly different, I can go there and do that without sending the party across a dozen nations and hundreds of miles. Yet, at the same time, I try to design these compacted features so that, while their borders are very close, they each stretch for quite some distance to give room for adventures. But it makes me wonder if I'm crowding climates together that are too radical to believe that the terrain could change so much so fast.
Please, help me with some feedback, and save me from my indecision!
This really depends on how long you are going to run your game. If your only going to run, say a few homebrew dungeons, then some simple villages with some woods and hills nearby and a lake would probably be enough, say 50 miles in diameter, just expand as your player show interest. If your going to be running a campaign of characters for decades; then you are going to need it all in a full world with various continents and everything.
Scaling of fantasy worlds is a common, but rarely noticed, issue.
If you look at a map of Europe and use a ruler to measure countries, you can get a good idea of the relative sizes of political units. Kingdoms could range in size from small ones the size of Denmark or Holland or Portugal, to large ones the size of France or Poland. City states and independent palatine duchies or counties might range from minuscule (the size of Monaco or San Marino) to merely tiny Andorra or Luxembourg, or the size of a province or county in a major European country--Tuscany in Italy, Kent in England, Rhineland-Palatinate in Germany are all derived from small, semi-independent political units of this type. An empire might range from the size of Germany, France and Italy combined (roughly the region ruled by Charlemagne) to the size of the Roman empire (basically all the countries bordering the Mediterranean Sea, plus England, Switzerland, Belgium, Bulgaria, Romania, and all of Germany, Austria, Hungary south of the Rhine and Danube Rivers). A particularly large empire might even encompass an area equal to all of Europe, including Russia west of the Urals--look at historical maps of the Mongol empire, which ruled about half of Asia, or various incarnations of the Chinese empire.
Keep in mind that medieval travel is slow and unreliable--it takes a lot of revenue and military power just to maintain a road and military postal system adequate to hold an empire like the Roman or Chinese together (the Mongols didn't build roads but had a legendary system of post communication in their heyday), so any empire that can't maintain that kind of revenue flow will tend to break up into separate kingdoms. Even France and England were pretty large and hard to hold together.
Also keep in mind that in medieval times, there was lots of trackless wilderness that was claimed, but not effectively ruled by various states. Think of Sherwood Forest (a relatively tame example), or the Black Forest, both of which were much larger than they are today. There are also even larger territories that have some kind of king as overlord, but the king has very little power over independent clan lords (think of the Alps, Pyrenees, or the Scottish Highlands). Leave big open spaces in the middle of and in between your kingdoms, where a few, but not many, human settlers live, and you'll have lots of room for dragons' lairs and abandoned wizards' castles and orc tribes and such, not to mention deserted stretches of bandit haunted highway between settled and civilized areas.
Finally, when you draw your maps, don't bother drawing clear boundaries. Surveyed boundaries are an artifact of surveying, which dates back to about the 17th century. Two kings might agree (or not) that a certain river or pass marks the boundary between their kingdoms. If the route is well traveled they might even maintain outposts and collect customs on the main highway. But people on both sides of the supposed boundary care about it only to the extent that the kings force them too. They smuggle goods through smaller, higher passes, herd their sheep on both sides of the ridge, marry their daughters to the family across the river, raid their neighbors and blame it on bandits from the other side of the border, etc. The language spoken on either side of the river or mountain ridge is almost the same, and quite different from the metropolitan dialect spoken in either capital--the border men might even speak their own language that is completely different from that of either kingdom (think Basque or Romansch or Suomi). The petty lords along the border may even owe fealty to both kings and have to choose which side to betray if there's a war, and may try to carve out their own kingdoms if the kings on both sides don't have a strong grip on power. Wars and marriages result in minor changes in the boundary all the time, sometimes without the knowledge or consent of the royal overlords. Valley A goes from Baron X (a vassal of King M) to Baron Y (a vassal of King N) as a dowry when X marries his daughter to Y's son.
Since surveying doesn't exist, you don't have to be very clear about the scale of your maps, either. You just need to remember (or take notes), so that if it takes 3 days to travel by horseback from City A to Town B one time, it takes roughly the same amount of time the next time the players make the journey (assuming road conditions haven't changed). On your master maps, you can just eyeball travel times based on the ones you've already established and you'll be fine. The players will never know, because even if you provide maps, they are rough. "If they complain, just say, your map must be a bit inaccurate. Surveying hasn't been invented yet, you know."
Sorry for the long post. I must be procrastinating. Hope this helps.
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I think there are places in the real world as "geographically busy" as you feel your kingdom is. I think the eastern part of Texas is a little bigger than your kingdom, and it has most all that stuff--there really aren't many lakes here, except manmade lakes, and I don't think Texas is famous for swampland. But forests, hills, and plains/desert we have in vast abundance.
Costa Rica, also, has a lot of stuff, in a really compact geographic area.
Bella Sara Charter Superscriber
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I think there are places in the real world as "geographically busy" as you feel your kingdom is. I think the eastern part of Texas is a little bigger than your kingdom, and it has most all that stuff--there really aren't many lakes here, except manmade lakes, and I don't think Texas is famous for swampland. But forests, hills, and plains/desert we have in vast abundance.
Costa Rica, also, has a lot of stuff, in a really compact geographic area.
I knew there were liches in Texas!
I would agree to use Europe as a base. Being from the States, I often tend to make massive countries like our lovely nation, but that really isn't likely. All of the largest nations of the medieval period were incredibly problematic.
Take for example, the fractured Holy Roman Empire. Or France, whose powerful nobles were often a great challenge for the King. Even look at Rome, which egan to fracture under the weight of its distance.
Now, this is real world, not fantasy, but I think it is a great guideline. Realize that most Medieval-inspired nations will be the size of Medieval European nations, and the larger ones could present problems.
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First, let me say that Peruhain's response covers much of the ground that I would, so I'll only make a few additions.
I always have the question in my head of "how big should this region be?" .... I want there to be enough room for all the adventuring I could possibly dream of putting in the region, but I don't want to make it so huge that it seems impractical, or each country so large that it would be almost unheard of for a traveling merchant or such to cross several kingdoms.
There are historical examples of nearly any size political unit you want. If you want something like China at the height of the Han dynasty, you get an empire that would take weeks to cross. If you want something like Germany in the middle ages, you can cross some city states in hours.
If you want a mix of little and big states, though, you'll probably want to decide why the little states haven't been swallowed up by the big ones. Usually, this would be the result of politically adept rulers of small states playing one larger power off against another (the Netherlands), coalitions of small states banding together for mutual protection (Holy Roman Empire), or remarkably defensible terrain acting as enough of a force multiplier to protect the smaller state (Switzerland).
Right now, I have the idea that a city-state's territory should cover anything from a 100-mile diameter or less, while a small country should by 101-200 miles across in its largest direction, an intermediate being 201-400 miles across, and vast kingdoms/empires covering everything above that, with an average ranging from 500 to 700 miles across.
I think all of your sizes are a bit big if you're trying for a European feel. 400 miles across is a major military power.
One of the effects of hereditary rule is to turn some areas into patchworks of diverse control. Take a look at the map of the Hapsburg Empire here:http://www.zum.de/whkmla/histatlas/germany/haxhabsbdaust.html
Much the same sort of patchwork territorial control could be found in Brandenburg-Prussia, Saxony, England, Spain, etc.
But, then sometimes I get into the mindset that, "You know, it doesn't really need to be that far apart...."
Villages are sited such that farmers can get to them regularly. In warlike areas, the farmers would live in fortified villages near enough to their fields that they could go out at dawn, farm through the day, and return in the evening. The result is probably a village every 3 miles/5 km. In areas of relative peace, where the farmers can live on their own farms, the villages can be a bit farther apart, because they only need to be visited every week or two. In wealthy areas where most farmers have horses, they can be further apart still, perhaps only every 10 miles/16 km.
Cities only arise where there is a really good reason. Usually this means transit choke points like river junctions, passes, oases, particularly good harbors, straits, and the like.
So, I'll go into a phase of designing things on a very small scale, only to come back and feel that it's all too crowded and needs to be redone, only larger and more spread out this time.
And it's not just city placement and political boundaries, but also, and mainly, geographical design....
Mountain ranges are caused by the crumpling of tectonic plates, by volcanoes, or occasionally by differential erosion. The appearances of these are very different.
Tectonic-plate ranges can be both very long and very wide. The Rockies-Andes range runs for perhaps 10000 miles; the Himalayas run the entire northern edge of India; the Urals run for thousands of miles through central Russia. (They can, of course, also be shorter; it's the length of the affected plate boundary that determines this.)
Volcanic ranges usually run shorter and patchier, though areas of vulcanism can be remarkably long. (See, for instance, the "Ring of Fire" that surrounds the Pacific Ocean.)
Differential erosion areas are often the result of subterranean magma intrusions being exposed. In these cases, the "ranges" are functionally volcanic. In other cases, you get "Badlands" like those in South Dakota.
I'd say that if you're looking for verisimilitude, you might be overusing mountains. (This was one of the problems with the map provided in "Seventh Sea".) National boundaries commonly run both on and far from natural barriers. Boundaries in flat and unobstructed terrain make for interesting conflict loci. Wars provide lots of good story opportunities.
Also, many boundaries combine good and bad terrain, which tends to channel conflict. The good terrain likely has a history of warfare.
HTH
Those really are some excellent posts, and I'm amazed at the speed which they appeared. Thank you all!
Saern is not a setting based strictly off medieval Europe. It is a D&D fantasy setting, and as such, I take heavy liberties with what does and doesn't work. So, I'm not really going for the sizing aspect of Europe; rather, I prefer the thought of vast, sweeping landscapes. Although, that doesn't necessarily translate into broad, sweeping political landscapes, I'm aware.
Take, for example, roads. A major issue in real world history, there is one factor that is extremely mitigating when one uses the Greyhawk pantheon (which I do)- Fharlanghn. The god of travel, his priests would spend most of their funding on building roads wherever they are needed, and maintaining them to the best of their ability. While certainly not interstate highways, that would give a road-building and upkeep situation centuries in advance of what was historically acurate to the other levels of technology found in typical D&D.
That said, I do like to base things off real examples. Completely by coincidence, the two small, patchy mountain ranges in the country are indeed volcanic.
I do draw exact boundaries on my maps, because I want to know, from a DM's standpoint, where things really are. I have also used the mental note, to players and myself alike, that the maps aren't perfect, but again, I draw them as acurately as I can to what I want, since I, as a DM, need them to be such. However, I typically do that in the broad scale when just planning something, and then go into the small scale and use more vague, natural boundaries to outline political boundaries.
One thing that I haven't been doing enough of, however, was the use of open, non-defined boundaries (the type that wars are often fought over) and general wilderness, ungoverned in all but name (and sometimes, not even that). Looking at my map of this and other regions in the campaign world, I find there are several areas that I can set aside as just such wilderness regions, and expand slightly upon them, which will serve to unclutter the maps of my more well-ruled countries. I could also stand to throw in more city-states as well. My countries are probably a little too cohesive, as well. I like the thought of that, but what I can do is shrink the area actually ruled (effectively) by the central government, and leave the surrounding region as part of the culutural landscape for those people, but beyond the central authority's actual control.
Looking back over the map of Merithil, I can see some obvious changes that could be made to give me the feeling and landscaping that I want. The other thing I can do is put a little more work into developing the surrounding regions more, so that I don't feel so confined to put everything I want into this one region.
Oh, and I plan on using this setting indefinately, perhaps even making novelizations of it at some point. So developing it well is very important.
Thanks again for that! I really needed a place to bounce some ideas off.
I would agree to use Europe as a base. Being from the States, I often tend to make massive countries like our lovely nation, but that really isn't likely. All of the largest nations of the medieval period were incredibly problematic.
Take for example, the fractured Holy Roman Empire. Or France, whose powerful nobles were often a great challenge for the King. Even look at Rome, which egan to fracture under the weight of its distance.
Now, this is real world, not fantasy, but I think it is a great guideline. Realize that most Medieval-inspired nations will be the size of Medieval European nations, and the larger ones could present problems.
I agree with Luke. Even if the region is large if you're using a feudal system the adventurers might pass through many diffrent fiefdoms ruled by the upper class, all in the same kingdom. During a turbulent time the land could conceivably switch hands during the party's passage, creating possible encounters with the victors. IMO the actual dimensions of the land aren't neccesary but in relative terms. For ease of travel the size of most european countries makes sense.
Yup, considering Europe...even some of the larger countries of today, like Germany and Italy, were unified only in 19th century and before that were a number of city-states and small areas which unified and split when necessary.
And as said, with feudal system even while the country in total would be large (like France), it would be divided to number of small baronies and so forth which make the political background, so for most purposes Alsace could feel like different country from Aquitania...
Even while one would go for large geographical features, one must consider travel of speed. If there is nothing faster than horses on meagre network of roads, you should consider medieval Europe as good model, political units from size of Monaco or Bremen to Tuscany or Normandy. Then in some cases you can group number of them together to make a larger kingdom.
Situation changes a bit on certain geographic or cultural facts. Nomadic hunters, gatherers and cattle herders have as a rule larger domains than farming communities do.
Also, if landscape is simple plain, it is relatively easy to travel and domains can be assumed to be larger. On the other hand, while area like modern-day Finland was forest-covered wilderness, there was an extensive network of rivers and lakes which made traveling much easier, both in summer and winter (betweentimes are problematic though).
I think Texarkana was founded by them.
I knew there were liches in Texas!
To badly mis-quote a famous country-western song, "All my liches live in Texas..."
All this true science in buiding your world is all good and well, but keep in mind that you can add a lot of extra flavor with magic and gods; perhaps; two gods had a fight that moved mountains and changed geography in strange ways during the course of their battle. One thing of not not mentioned when talking about borders as they typically have geographic origins based on impeeded travel; ie; rivers, mountain ranges, cliffs or vast chasms or continental divide. Strength and size of a nation is directly in proportion to resources available and their ability to claim and process these resources. Additionally, there are 7 basic climates; you may wish to have all these or more that way your players can experience the artics and a blistering desert; my players mostly fear swamps for example.
just some things to keep in the back of your head.
To badly mis-quote a famous country-western song, "All my liches live in Texas..."
"And thats why I hang my shield in Tennessee..."
Additionally, there are 7 basic climates; you may wish to have all these or more that way your players can experience the artics and a blistering desert; my players mostly fear swamps for example.
My players dread swamps as well, just because of the abysmally slow travel and all the incessant nastiness that lives there, particularly when they're drudging through the aforementioned undead-and-cold-plagued swamp. However, what really got them was a very short campaign where a ship was leaving to explore another continent, and they landed on the shore only to find a vast swamp. They started off inland, and after several days of travel, the wizard flew up in the air as far as he could, and all he could see was swamp. I had plans for them, but they got tired of it at that point, went back to ship and said, "Let's go home, there's nothing here."
And your points are very good about magic. I like all the information about real world history, but one has to remember that magic, both divine and arcane, really exist in D&D, and thus play a major role in shaping of political boundaries. Countries can be a little bigger if there are enough mages to teleport important officials here and there when in an emergency. If the kingdom can make a pact with a dragon, the prospects of any rebellion become seriously diminished.
Back to geography, I've also noticed that, quite by accident, most of my major kingdoms are located along the sea, which I realized, upon thinking about it, made a lot of sense. So that's another thing I can keep in mind when designing new areas from now on, too.
I like to imagine a large number of my countries to be better than a feudal system, at least in terms of living. The world I've designed is, again, a D&D world first and foremost, and it seems to me that the general example thereof shoots for a technological, architectural, and cultural model closer to the year 1300 or even 1500, rather than 1100 or earlier. Of course, feudalism was still very popular, but it was on its way out, nonetheless, as an emergent middle class and mercantilism returned the European economy to a solid foundation and even allowed it to grow and thrive in areas. Nations started consolodating a bit and growing larger, although this really didn't happen in full until several centuries later.
Just some more observations.
And some other world-building issues- guilds and organizations. Those on an global, international, or even national level are easy to size up- "They're huge." You don't worry about roughly how many members are in it. But, when you have a local, perhaps only city-wide guild, it becomes a lot more importnat, especially if the party calls on them for aid or runs afoul of them and plans on doing battle. I'm thinking mainly along the lines of local mages' guild halls, temples, etc. How big, by membership, should such things be in a smaller city, an intermediate city, and a large city/metropolis?
Thanks again for all the assistance! I've got some good ideas to go with now- smaller countries with more unclaimed areas around them, rife with orcs and dungeons, and just what Joe Adventurer is looking for.
I have let my characters do most of the foundation work for guilds, I just start with a guild sketch of a few npc's and as the needs of a player increase I add to needed guilds; there really is not reason to do all the extra work ahead of time if players never encounter that particular peice of work; I have wasted quite a bit of time with this when I was a young gm. It is pretty easy to keep ahead of the players as you are controlling the plot line. As for maps; I highly recommend you make a gm map and a player map; yours filled in and theirs with only key terrain features and known things that they fill out as they explore; I have found this works very well and some players take a real interest in keeping up the maps.
Oh, yes, I already understand that, but what I'm wondering is more along the lines of, "Should the mages' guild of this small city have 10 members, or 25, or what?" just as a general rule. I can make the further details as they become necessary, or on the fly with the DMG if needed, but I'd like to know at least a general idea of how many people such a group would have on hand at any given time. Same for the average temple. I find that very useful to know.
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... they landed on the shore only to find a vast swamp. They started off inland, and after several days of travel, the wizard flew up in the air as far as he could, and all he could see was swamp. I had plans for them, but they got tired of it at that point, went back to ship and said, "Let's go home, there's nothing here."
And Smaug lived happily ever after. 8-)
And your points are very good about magic. I like all the information about real world history, but one has to remember that magic, both divine and arcane, really exist in D&D, and thus play a major role in shaping of political boundaries.
Your world; you call. That said, I think you might overstate the effect of magic. Unless your world has a major differential in magical availability between countries, I would broadly expect a balance of power, at least between major powers.
Countries can be a little bigger if there are enough mages to teleport important officials here and there when in an emergency.
Communications is the big issue, I think (and as you tacitly suggest). If there's a big difference between the communications capabilities of the sides in a conflict, the result can be rapid devastation. For a historical example, see the German invasion of France in 1940 - it was communications that made the biggest difference. (Again, though, I'd expect broad parity here.)
If the kingdom can make a pact with a dragon, the prospects of any rebellion become seriously diminished.
Unless, of course, it's the rebels that make the first pact (or create the first dragon-slayer spell, or the first protection from a dragon-slaying spell, or ...).
You might want to think about the possibility of a magical equivalent of a hydraulic empire. If a king can control access to magic, he could reasonably perpetuate and extend his control over other things as well. (For an overview of the concept of a hydraulic empire, see http://en.wikipedia.org/wiki/Hydraulic_empire, for instance.)
Back to geography, I've also noticed that, quite by accident, most of my major kingdoms are located along the sea, which I realized, upon thinking about it, made a lot of sense. So that's another thing I can keep in mind when designing new areas from now on, too.
Historically, the sea has provided protection, communications, trade, and food. Interestingly, I suspect that intelligent sea creatures would reduce the value of the sea. Such civilizations might reasonably object to ships sailing through their "fields", fishermen raiding their "herds", passing traders dumping trash in their "streets", or whatever. And they may well have the means to enforce their desires.
How big, by membership, should such things be in a smaller city, an intermediate city, and a large city/metropolis?
Guilds (again historically) were all about rent-seeking. The object was to limit competition to increase prices. So the answer would probably be something like, "A bit smaller than the city can support." How big that really is will depend on the prevalence of magic in your world. In a world with magic as common as that in Eberron, I'd expect multiple guilds differentiated by specialty. In a low-magic world, I'd expect a bare few mages in a medium-sized city.
Yup, communication is major issue as is being able to enforce the law. American Wild West pops to mind as good example...China managed to handle a large empire, mostly by being very center-oriented in doing it...all the officials were trained in same manner, sent to provinces to rule and were also shifted a lot around so they didn't become too entangled on local schemes.
Of course teleportation, if relatively common, changes the scene as does flying or communication over distance (having a crystal ball network to cover province officials is something every fantasy kingdom should look to...it will be so worth the price). Big reason why most large cities and kingdoms are situated on coast of the sea or by large rivers is that traveling by sea was the fastest method for a long time. Situation would change completely if, say, ley lines crossing the land could be used to major teleportation magic.
Prevalence of magic is a big issue, I've come to realize. The world I've built is the type where it is rare amongst the populous, rather like Greyhawk or some versions of the Forgotten Realms, but on the national level, major and even intermediate kings have ready access to fairly vast amounts of arcane power.
Many worlds feature a fallen empire similar to Rome, which fell centuries ago and the world is now rebuilding from that. This setting is similar, even to the point of having a Rome-inspired empire in its history and some areas that continue in that cultural tradition. However, the most recent empire was a magocracy of immense power, which covered half the known world. Though gone for four centuries, there is still quite a bit of their stuff lying around, and many lineages of kings latched on to the secrets of how to continue making at least crude copies of these things shortly after the collapse of the empire, thus explaining the royal access to magic. I hadn't really thought of instituting such restrictions on magic as a means of control, but I will now. Thanks for the suggestion.
By "magic shaping political boundaries," I wasn't meaning that whoever had mages wins, since as you pointed out, there is a relative balance of power. Rather, I meant that magic is employed by several major nations as a form of border patrol- walls that alert the generals of the kingdom when they are breached, lines of magical turrets which fire upon those attempting to cross boundaries, etc.
In thinking about it, the world isn't really uniformly of one magic level. Some areas, where the aforementioned empire ruled, are high magic, while others that were not so important to the ancients had less magical power available and continue in that tradition to the present.
Another point is that, as in many worlds, there is a long history of demonic invasion. However, I REALLY like fiends, so I made this a major feature of the world history, rather than just a footnote as seems to be common elsewhere. The remnants of their war against mortals over three millenia ago still produce some dramatic magical phenomenon the world over.
This thread is possibly one of the best for advice on world building that I've seen. I hope everyone who is designing a setting that they plan on sticking with for a long time reads this, because the advice I've seen here is top notch. I've already done so revisions and re-drawings of my maps, and I immediately felt better about the spacing and placement of various features. Now I just need to wrench myself away from world building and back to designing adventures....
Just because powerful magic exists doesn't mean it will be applied to it's possible maximum utilization. There are many examples of a technological invention not having much effect at one point in history then becoming a big deal sometime later or somewhere else. The Sumerians and Incans both had the wheel. The latter used it only on children's toys. There were steam engines in Ancient Greece, but they were used to open temple doors without the touch of a human hand, not to propel trains down tracks or loom fabric. Etc.
Saern,
Do you have a digital map that you can put online or email? I would love to see your world. I could offer feedback if you like. I have a BS in geography and have worked in mapping industries for 13 years. Of course fantasy maps are different than the governmental stuff that I work with.
I was going to put a long post about how I make new worlds, but I think you are beyond this point. I would like to mention that I assign creatures early on in the process. That way, I know that I want Yak Folk and orcs and demon worshipers and can leave room for them without doing major rework later.
WM
Apart from the existence of magic in D&D, the other force which sets a standard D&D world (let's use the baseline of Greyhawk) apart from Earth's medieval period (let's use western Europe) is the inclusion of other intelligent organized races. By this I don't just mean elves, dwarves, and halflngs, but also orcs, hobgoblins, and any other humanoid race you can think up. The mindset of an elf or dwarf is in many ways completely alien to the minset of a typical human and this affects every facet of their society, culture, and the way they interact with their environment.
In the medieval world political boundaries were seldom defined and constantly in flux, yet a kingdom ruled by dwarves with their lawful mindset would most likely have tightly defined boundaries. On a broader and more sweeping scale, elves with their love of forests and use of magic could shape an entire forest to look like whatever they wanted. There are also questions like do orcs despoil the areas they inhabit (leading to vast areas of unusuable wasteland)? Do goblins act like lemmings when they overbreed and attack the human cities in a way similar to lemmings running off a cliff? (its not the same of course, since lemming drives are not just about overpopulation and attacking a city is a big task, but I think you get my drift). Do dwarves build their cities underground and have underground highways connecting their communities?
World-building is a very difficult task, and you have to answer a lot of questions, but the scope of your campaign and the needs and desires of the players will determine much of what you have to sketch out about your world. Just remember that your world exists not just to satisfy the needs of your players and should seem like a living breathing entity that continues on whether they live or die (unless they are high level and trying to save the world from destruction ;)). You are a very intelligent person though, and I have faith in your ability to make it all work out.