In North Central Florida where temps get up to 100 or 110 (we're not on the coast) AC feels like it is necessary but I've known of people who have lived here without it. A series of fans and knowing which windows to leave open and when is the key. It's all in the construction of the house too. When people immigrated from Europe to the southern United States the typical construction of these houses was a very tall house with giant windows which open up. Since heat rises these early houses were built around this premise and people around here have been here a long time. Otherwise ice arrived by train and was placed next to a fan which was mechanically operated or by hand in the old days. My native ancestors from this area lived in log cabins (not teepees or huts as commonly described in history books) and the wall-less thatched structures were communal gathering spots not their actual homes. Modern construction with all the prefab elements and insulation is suffocating in my opinion and this is why, by choice, I live in a wooden house although yes I do have AC and enjoy it very much.
I'm from FL and I remember houses used to be built to help with the heat. It was still hot, but you'd have porches and eaves to block the sun and windows situated such that you could open them to create airflow through the house. Now, everything is a sealed box so AC is absolutely necessary.
