Why Did the Eastern Half City （Left Capital） of Tang Chang＇an City and Japanese Heijokyo and Heiankyo Capitals Become More Prosperous？

摘要

In the second year of Kaihuang 开皇 reign (AD 582), Sui Dynasty Emperor Wendi 文帝 issued the decree of constructing a new capital, which was called Daxing 大兴. After the founding of the Tang Dynasty in the first year of Wude 武德, reign (618), this city remained the capital but was renamed Chang'an.