Guns, Germs, and Steel (1997) by Jared Diamond would certainly would seem an odd choice for an RPG blog but it raises interesting ideas that could serve as inspiration when populating a newly created world (or newly discovered continent).
In this book, Diamond posits the idea that the availability that large animals that easily domesticated and of good grains and pulses in an area is the primary determining factor in the rate at which societies transform from hunter-gatherers to settled food producers. He also argues that this allows for much higher population densities and the specialization of labor, two factors critical for the development of technology higher than stone-age tools. Diamond also shows technology spreads through diffusion to neighboring societies in inverse proportion to their degree of isolation.
Interesting enough, but how can this be useful in a role-playing game? While this idea would certainly be of very limited use in an ongoing campaign, However, these theories about the distribution of technology can aid a game master in world creation.
If a world in which the technology levels are relatively even, then the GM can assume a widely diverse group of easily domesticated grains and pulses grow on each continent and that there are also large, easily domesticated animals on each one. Without both of these, a society would advance much more slowly and have less incentive to move away from a hunter-gatherer lifestyle.
For example, lets say that a GM has an ongoing campaign and wants to add a large island (roughly the size of New Zealand's North Island) on which there are the ruins of an ancient civilization and living dinosaurs. The GM has located this island roughly half-way between two large continents, one with a medieval European style society, the second with a medieval Asian style society. The GM wants there to be people on the island to be able to lead the characters to the ruins, but doesn't know what there society should be like. First, the GM should determine how isolated this island is. In this case the island is extremely isolated with it lying outside the shipping lanes between the two continents, which are rarely used. Because of this, the inhabitants of the island will have been limited to whatever technology they brought with them (almost certainly good stone age technology) and what they developed there.
Next, following
Guns, Germs, and Steel, the GM should look look at potential food sources. Because there was a civilization developed enough to leave ruins behind, there was very likely at least one good grain or pulse available, but the size of the island makes it extremely unlikely that there were many. As for there being large easily domesticated animals, the obvious answer is no. With the island being home to dinosaurs, no large mammals or birds are likely to have evolved leaving only the dinosaurs which would been far to aggressive to domesticate, though a few may have been a few charmed or even tamed. This leaves us with a civilization that at its peak was depended upon a very limited number of grains (likely supplemented by fruits and vegetables which are great but don't store well) with no large mammals. While there may have been a few chickens, hunting will have likely been the main source of meat. The lack of large mammals to pull plows, carts, etc. and the reliance on hunting would make the society more labor intensive and allow for fewer individuals being able to specialize in anything other than food production/gathering. Fewer specialists means much slower development of technology. This society, while advanced enough to leave ruins, was very unlikely to have advanced beyond stone tools (obsidian if the island is volcanic) and beaten copper jewelry. From this we have an isolated society that in some ways may have resembled the ancient Mayans.
This leaves two important questions. How did a stone age civilization arise on an island overrun by dinosaurs and why did it fall? The first, although it would be utterly impossible in a mundane world, is easy in a fantasy world. Magic! Only if the inhabitants had powerful magic when they arrived could they ever advanced beyond terrified hunter/gatherers living in caves to avoid the larger dinosaurs. Interestingly, the game system being used might make a difference here. In most old school systems, this would mean that the society was literate and that there will likely be magic scrolls (not necessarily rolled or on paper), spellbooks, maps, glyphs, etc. for treasure. However, if the game system allows sorcerers, there is no absolute need for literacy and it would be completely up to the GM to decide. Regardless, this means that these ruins will likely have many magic items and magical traps, but only simple mechanical traps.
For the second question,
Guns, Germs, and Steel and Mesoamerican history provide the easy answer. Crop failure. Being dependent on a single grain, a society could not survive it failing for a few years. At some point in the distant past, a crop failure occurred, likely a crop disease that greatly reduced food production. As the people starved they turned against their magic user leaders and slaughtered them, and in the process left their civilization defenseless against dinosaurs. The few survivors would have had no choice but to adopt a hunter-gatherer lifestyle going wherever the food was and learning how to avoid the dinosaurs.
When the characters arrive, they will find an extremely primitive people who have become experts in stealth to avoid being eaten. They will know where all the ruins are and know which ones are safe to hide in and which are dangerous (magic traps, undead, etc.). One complication that might cause distrust between the characters and the locals is that they will have far less resistance to disease than the characters and anyone who accompanies them (sailors if they arrive on a ship). Because most dangerous diseases have their origins in domesticated animals and the locals have not been exposed to them for millennia, if ever, they will not have the resistance that people from more developed societies (the characters) have. And although primitive, the locals are not stupid and will draw logical, though wrong, conclusions. Strangers arrive, we help them, we are struck by a curse, therefore the gods are angry that we helped them.
From just a few very basic concepts, isolated but inhabited island, dinosaurs, and ancient ruins,
Guns, Germs, and Steel has helped to flesh out the beginning of what could be a fairly original and logically consistent adventure or campaign. This book was both a best seller and a Pulitzer Prize winner, which means that it will be available in most libraries for the frugal game master.
