Conhistory/Geography and Its Effects
Smaller Landform Features
Mountains and Valleys
Mountains form near where tectonic plates collide, this may lead to earthquakes, floods and volcanic eruptions (or even tsunamis if near sea). Older mountain ranges tend to be eroded, and solitary mountains are usually volcanic. They often limit precipitation in the surrounding area, so deserts nearby are not uncommon. Until technology is developed which allows relatively safe passage through mountainous areas, mountains make for excellent natural defences for early civilizations. Any people who live in these areas and who do not rely on lower altitudes to grow food or keep livestock may be able to survive long periods of time without being invaded by others.
Rivers and Lakes
A few rules to follow concerning rivers is that they always flow downhill and never branch except when near a body of water. Because they nourish the soil around them and provide a method of transportation, settlements will often form around them. Trade can flow easily around rivers and people travel with them leading people further afield.
Climate (And Differences)
Most civilizations flourished on the enhancement of the elements. Arabs found water in the desert, Dutch Land out of marsh and so on. If a civilization lived in several environments it could enhance one and leave the rest uninhabited or enhance many and prosper.
Civilizations tend to use nearby resources wherever possible: A civilization with access to trees may build wooden houses whereas a civilization near a river uses bricks and writes on clay tablets. Scarce resources have to be obtained by trade or by military means.
Proximity to Others
Greater Landform Features
The Fertile Crescent
If designing an entire world from the earliest days of civilization or an extremely old nation, thought should be given to where on the planet civilization is likely to evolve first.
Civilization is widely believed to have originated in the Middle East, more specifically in a band of land called the Fertile Crescent. This area encompasses four major rivers. Starting with the Nile River in the west, the Crescent contains the Tigris and Euphrates rivers and finishes with the Indus River in the east. All rivers, when they flood, deposit large amounts of mineral-rich silt on the flood plan, which are excellent areas to grow crops. It is believed that having so many of these highly fertile rivers in a concentrated area, allowed the early inhabitants the opportunity to grow more food per hectare with the same amount of labour that would normally be required. Thus, as fewer people were required to toil the land, labour could diversify and individuals could begin to specialise in other roles, such as warfare, science and medicine.
East and West vs. North and South
It has been said that one of the reasons that Eurasia tended to develop more quickly than the Americas as a whole, was the difference in their shapes. Eurasia mostly had distance going east and west, while the Americas went mostly north and south. When going north and south, there are various climate changes, so people generally don't travel far in those directions within a lifetime of their own accord. When going east and west, people are more prone to traveling great distances because the climate varies less often. Thus, technological and ideological advances are more likely to extend east and west, instead of north and south. Thus, Eurasia was more likely to share its advances. For example, the Maya developed a system of writing that never went south to the Inca, or north to the various areas there. However, writing in Eurasia spread easily after development. Writing, in and of itself, (not unlike computers or the printing press), speeds up technological advances because things can be saved through time verbatim in the written word, as opposed to more questionable oral tradition.
Jared Diamond, in his 1997 book "Guns, Germs and Steel", put forward the theory that while agriculture appeared around the world, it was the amount of animals and crops available for domestication that gave early Eurasians an advantage. In contrast, early Native Americans struggled to develop maize as a viable food. It needed to be planted one-by-one by hand (which is labour-intensive) and is low in nutrients. In Eurasia, however, the inhabitants had wheat and barely which was not only highly nutritious by could be sown by scattering the seeds in a field. This allowed more food to be grown, thus supporting a higher population. Furthermore, grains can be kept for a much longer period than tropical foodstuffs such as bananas. What may also have aided growth in early Europe, Diamond argues, are the similar climates found at different latitudes of the continent. If temperatures and conditions remain the same for the majority of the year, then the same crops can be grown in much wider areas. The domesticity of animals also may have played their part in that while sub-Saharan Africa has primarily wild animals (lions, hippos and elephants for example), the animals of Europe were much easier to tame.
Ocean vs. Land
Obviously, unless you have amphibious creatures and/or vehicles, going over the ocean is not the same as going over the land. Oceans pose interesting military possibilites. If one nation develops an extensive navy, that nation may be able to rule the seas and use it for trade and transportation, whilst limiting the ability of others to do the same without permission. To other nations, the seas now become a limiter. To nations without the ability to construct seafaring vessels, it may become almost impossible to cross the seas. If your race is somehow water-based, the opposite may be true. Either way, it is almost impossible to amass great numbers across a distance in a short time over water without a great ability to transport people. Fishing is also a way of making a living for people. Coastal cities often develop for their ability to transport goods from land to sea quickly. Japan is especially capable of this, for example, because virtually every point in that country is less than two hundred miles from the coast. They also have a very large fishing industry.