As a fantasy/sci-fi writer – so I claim – I often get to a point where I have to ask the most basic of questions, a question that seems simple at first, but really has powerful consequences in my writing.
What is the driving force in this country?
However you answer this, and there may be more than one, determines how things can reasonably play out. Those six factors are the driving forces behind most events in history. They shape a country, and guide it down the paths it must take. However, it should be noted that they overlap. There is almost always two or more driving events, as one gives, another takes.
If a country’s driving force is military superiority in a medieval setting, they probably have solid blacksmiths, and a large population that weakens their food control, thus pushing a more war-mongering kingdom. Remember as population increases, so does resource consumption.
The invention of the firearm was a major advance in military combat. Nobunaga Oda, of warring states Japan, was quickly feared as he was able to easily defeat the legendary Takeda cavalry with simple barricades and rifles.
Ever hear of the Inquisition? How about the Crusades? Religion with political control turned into horrible genocides in the name of Christianity.
A shift in power could lead to a country breaking up into smaller countries, creating several new economies where there was once one, sending global economics into an upheaval.
But what about Magic? It seems to be an oddball here. Well, I include it because I like to write fantasy. As such, magic can become a driving force for a country. It can be what bolsters its economy, its military, its science! A religion can be built around magic if we so choose. That’s why it’s an oddball in the list, but just as important.
I’ll leave this off here, as I don’t know how much more I can go into a broad subject range without needing to get into specifics on all of the topics. Needless to say, there is plenty to work with from there, and more if you put your imagination to it.