This is far from exhaustive but it outlines more or less the train of thought I go through when worldbuilding. It currently lacks my magic system worldbuilding but I’ll likely leave that for another time (if anyone cares for it, that is lol)

Societal/cultural:

1) How advanced is this world? What kind of technology are we seeing? Weaponry? Enlightenment? Civil unrest?

2) How involved in the culture are the people? Does it dictate much of their lives? Do most citizens follow a set of several cultures? Is the country a cultural melting pot?

3) What is the geographical location of the country? What influence does it have on the people? What sort of lore comes along with it?

4) How different is culture from religion? Do they influence each other? Are there multiple religions/cultures in one country? If so, how do they interact with each other?

5) Are there castes in place in your country? If so, has there been any attempt to change this? Are the people happy in their castes or have revolts taken place?

6) What is the geographic landscape of the country? Have the people exploited the land? If so, for what purpose? Does culture influence their readiness to exploit the land? Does it influence how they treat it?

7) What are the religions of the other countries? Are there common beliefs? Where have they diverged? How does this affect their relations?

Linguistic:

1) What is the predominant language spoken in the country? Are there minority languages? Is it shared with the neighbouring countries? If not, is there a lingua franca (common tongue)? If so, what is it? Why is it the lingua franca?

2) Of the minority languages, why are they in the minority? Are there other dialects? What kind of relations does this cause among the peoples? Is language seen as an economic distinguisher?

3) Are the languages in the area of the same family? If so, what are the changes? If not, is there overlap? Where did the other language family come from? Do they influence each other? Consider loan words and where they may come from.

4) Does your country have multiple official languages? Does it have an official language at all? What purpose would it serve the people (culturally and politically) to have or not have an official language?

5) What stereotypes come with different languages? Do these stereotypes serve cultural or political agendas?

6) What influence has culture made on language? Consider profanity – in English, it’s centred around bodily functions, but in French, it is religious. Euphemisms and idioms are often heavily influenced by culture.

Economic:

1) How does the country’s geographical placement influence their relations with other countries? What resources might they have that others lack? What resources do they lack that they require?

2) What is the country’s economic state? What is their state like in comparison to neighbouring countries? How do the people feel about this?

3) What resources are being traded? How? In what demand is this resource? Does the country trade fairly or unfairly for these resources?

4) What is the currency of this country? Do they share a currency with neighbouring countries? If not, does this cause complications?

5) Who is in charge of economic spending? Is the policy fair? Do most people agree with the policy? Do they have a voice in the matter?

Political:

1) What kind of government is in place? What are the politics of this country? What are its relations with neighbouring countries?

2) How are their religions influencing their politics? What influence do the clergy have on politics? What influence do the neighbouring clergy have on the politics of the neighbouring country? Does this impact relations? If so, how?

3) What is commonly discriminated against? Why so? Is this the same in neighbouring countries? Was it always this way?

4) How do the people feel about their government? Does this vary based off demographic? Has anything been done by the people in protest? Were they successful? What did it look like?

5) What policies are in place? Do they please the people? Do they greatly favour a single peoples in a country of many nations?

6) What nations live in this country? Do they consider themselves distinct? Are they assimilated? Are they free to practice their own culture?

Technology:

1) How did culture influence their weaponry? What makes them different from their neighbouring countries? What does their warfare look like?

2) Is there a reason for the current type of warfare? What, historically, could have happened?

3) How far along is the technology? Is warfare their primary focus? Have technological advances been focused on other things?

4) What advances have come from other countries? How did they receive them? Who is it available to?

5) Has technology influenced fashion? What innovations have facilitated the creation of clothing?

6) How has technology affected day-to-day life? What innovations have trickled down to the general public? What was the origin of this technology?

7) What technology/materials do they need to import from other territories? Why?