How did weather affect first nations people?

Answer 1

Very much!
That is why we have no progress far away from the 33rd to 38th parallel, especially in the classical times.
Thus, the ones North of it, tried to claim lands there, while the ones southern did not even have the mental strength to move, except for attacks from others and animals.
The ones in the north did not make any significant civilization while fire and sun played important roles in their religions.
Those of The south did not developed anything significant.
Not of them developed any cities, except those between the 30th to the 40th parallel, showing the more collaborative methods developed.
Thus, the first civilization was created around the 35th parallel, and more specifically in the coastal Greek areas.

Answer 2

Weather affect the nations of people in term of their food they eat, clothes they wear, lifestyle, culture, and even religions.

People living in colder countries, eat more fats and oily food to keep warm, compare to those living in the hotter region.

Those people living near the equator - countries Indonesia, Singapore, and Phillipines, wear more casual clothing, such as T-shirts, shorts and slippers. Whereas those living in the northern region wear more thick clothing, and wear shoes most of the time.

I personally believe that weather affect the lifestyle of the people, their behaviour, thinking, attitude, social behaviour, and even the intelligence...The food they consume make them what they are and even the skin complexion.