Luoyang was regarded as the capital of these dynasties mainly because of its superior geographical location and unique natural conditions. Luoyang is located in the Sanchuan Valley, which is a small plain alluvial by the Luohe River, the Yihe River and the Yellow River. Luoyang lies to the north of Luohe. In short, Luoyang, which was located in the middle of the dynasty at that time, really became the capital of the dynasty because of its retreat to the terrain and convenient water transportation.
But none of these dynasties really flourished-the Eastern Han Dynasty, the Western Jin Dynasty, the Northern Wei Dynasty, the Sui Dynasty, the Tang Dynasty and the Five Dynasties and Three Dynasties.
From Guangwu Emperor Liu Xiu to the last emperor Han Xian Di, the Eastern Han Dynasty always took Luoyang as its capital, leading the world and governing the four seas. At this time, Luoyang became the center of the country, and its economy and population even surpassed Chang 'an, the capital of the Western Han Dynasty.
In fact, at this time, both Cao Wei and the Western Jin Dynasty experienced the Three Kingdoms Rebellion, Chang 'an was often occupied by foreign countries, so it was relatively peaceful, and Luoyang, the birthplace of the gentry in the north and Kanto, naturally became the capital of Cao Wei and the Western Jin Dynasty, which was dominated by Yingchuan Haozu. These two dynasties were not many, because the time was short, in fact, Luoyang at that time had not recovered to the prosperity of the early Eastern Han Dynasty.
As a Xianbei dynasty, after the Northern Wei Dynasty made Luoyang its capital, it also brought about ethnic integration, and Luoyang began to prosper. Coupled with the rise of Buddhism and the integration of other ethnic groups, Luoyang at that time became an international city, and its prosperity even exceeded that of the Eastern Han Dynasty.
After the Sui, Tang and Sui Dynasties dug the Grand Canal, Luoyang also became a transit station between the north and the south by virtue of the Grand Canal, ranking first in the country in terms of prosperity and commercial strength. By the time of Wu Zetian, Luoyang City had expanded again, with a larger population.