枢軸時代
The Axial Age and its aftermath saw large wars and the formation of large empires that stretched beyond the limits of earlier Iron Age Societies. Significant for the time was the Persian Achaemenid Empire. The empire's vast territory extended from modern day Egypt to Xinjiang. The empire's legacy include the rise of commerce over land routes through Eurasia as well as the spreading of Persian culture through the middle east. The Royal Road allowed for efficient trade and taxation. Though Macedonian Alexander the Great conquered the Achaemenid Empire in its entirety, the unity of Alexander's conquests did not survive past his lifetime. Greek culture, and technology spread through West and South Asia often synthesizing with local cultures.