Why did the rise of classical civilizations and classical belief systems occur at the same time?

Enough of that Foundations garbage.  That was only 5% of the test! You could literally not know any of that and still get a 5.  So, let's put on our 'big-boy-pants" and start covering some real history.  This is where it all begins.  Yeah, in Foundations you have things like... Humans, Fire, Tools, Hierarchy, Religion, Writing.  But, this is where history actually takes form.  This is where you will get your stereotypical views of certain areas.  This is where Western Europe takes root.  This is where India becomes India.  This is where China becomes China. Later on, areas like Africa, the Middle East, the Americas, et al will come into their own.  This era really deals with the Classical Civilizations (Mediterranean, India, China) and the trade between them and what goes along with that.