The characteristic trade of silk through the Silk Road connected various regions from China, India, Central Asia, and the Middle East to Europe and Africa.
The history of Asia can be seen as the collective history of several distinct peripheral coastal regions such as, East Asia, South Asia, and the Middle East linked by the interior mass of the Eurasian steppe.
In southern Mesopotamia were the alluvial plains of Sumer and Elam.
This was the basis for the Vedic religion, which would eventually sophisticate and develop into Hinduism, a religion based on the caste system of class (which consisted of the four varnas), the brahman priesthood, and the developing semi-monotheism.
The centre and periphery were kept separate by mountains and deserts.