Analysis of information sources in references of the Wikipedia article "Axial Age" in English language version.
Hermits and wandering thinkers in China, ascetics in India, philosophers in Greece and prophets in Israel all belong together [...] [peripatetics founded] schools which are termed academies by sinologists: the sophists and philosophers of Hellas travelled about in similar fashion and Buddha passed his entire life in wandering from place to place.
This is the Axial Age period, the period of the emergence of the second generation civilizations.
Not until the first millennium BCE do the first universal religions appear. Though associated in practice with particular dynasties or empires, they proclaimed universal truths and worshiped all-powerful gods. It is no accident that universal religions appeared when both empires and exchange networks reached to the edge of the known universe. Nor is it an accident that one of the earliest religions of this type, Zoroastrianism, appeared in the largest empire of the mid-first millennium BCE, that of the Achaemenids, and at the hub of trade routes that were weaving Afro-Eurasia into a single world system. Indeed, most of the universal religions appeared in the hub region between Mesopotamia and northern India. They included Zoroastrianism and Manichaeism in Persia, Buddhism in India, Confucianism in China, and Judaism, Christianity and Islam in the Mediterranean world.
The emergence of this specific type of Axial Age breakthrough was connected with the special mode of disintegration of the tribal communities and of construction of new collectivities and institutional complexes. [...] In the economic field, we find a growing occupational differentiation between the economic ties to the land and the urban vocations, be they in trade, craft, industry, or the ritual and educational fields. This phenomenon was also very closely connected with the development of many free economic resources—partially even land and manpower resources—not bound to ascriptive social units, the concomitant development of widespread internal and external, relatively free, market activities, and the accumulation of relatively mobile capital.
