After the end of Pleistocene (Ice Age) we entered the Holocene. THe early Holocene was marked by perfect temperatures world-wide, much warmer than today by several degrees. Carbon Dioxide was measures higher than today. Farming was at elevations some 1500 feet higher up slopes than today. Growing seasons were longer.
Ever see those corpulent goddess figurines? It was the Goddess age as humans had plenty of food supply and mated like bunnies to replenish the species following the massive floods of the end of the Ice Age.
Wars were non-existent because there were no worries about food.
This period lasted a few thousand years then the climate turned cold. Farming was harder. Food became scarce and roving bands of bandits went in search of food. Cities were now built with a fortress like mind.
Climate has much to do with human society, but it is a much warmer climate rich in CO2 that creates optimum living conditions.
Why do I know so much about this? I have been researching all of this as part of a book that I have been writing that spans pre-and post ice age.
Al Gore and his ilk are full of bunk. Does man affect climate? Yes, of course, locally or even regionally. But the Earth and the Sun as well as the Solar System have much more to do with our climate than man does.
For example, one way man affects climate locally. Take a city with all that asphalt. Local temperatures will increase due to the heat rising off the pavement at night. Slash and burn agriculture can also affect climate locally. But Volcanoes affect things globally...arrghhh.
Add to list: “... the Earth and the Sun as well as the Solar System ...” ocean currents and volcanism.
Just be glad no one is advocating a return to the O2 levels of the Triassic and Jurassic ...