So what is the ancient capital of Xi 'an? In my opinion, the capital that a dynasty can rule stably for at least a period of time is still counted. If it is the capital of Emperor Gengdi, it is not appropriate to count as an ancient capital. However, although the capital was only settled in Xi 'an for a period of time, it was included as long as the dynasty was stable for a long time.
This can be considered as the ancient capital of the Thirteen Dynasties, that is, the capital of Western Zhou, Qin, Western Han, Xin Mang, Eastern Han, Western Jin, Former Zhao, Former Qin, Later Qin, Western Wei, Northern Zhou, Sui and Tang Dynasties. Of course, if we only consider the unified dynasties, there are Zhou, Qin, Western Han, Eastern Han, Western Jin, Northern Zhou (after the Northern Qi Dynasty was destroyed), Sui and Tang Dynasties, and there are quite a few.
The key lies in the Eastern Han Dynasty and the Western Jin Dynasty. Many people will say, no, Luoyang is the capital of the Eastern Han Dynasty and Luoyang is the capital of the Western Jin Dynasty! Let's talk about the Eastern Han Dynasty. In the process of historical development, especially in recent years, the capital of the Eastern Han Dynasty was first moved to Xuchang and then moved to Xi 'an, thanks to Dong Zhuo. The same is true of the Western Jin Dynasty, with Luoyang as its capital and Xi 'an as its last five years. 3 1 1 year, Liu Cong captured Luoyang, the capital of the Western Jin Dynasty, and captured Emperor Huai of Jin Dynasty, while the army of the Western Jin Dynasty established Yu in Chang 'an, which continued the regime of the Western Jin Dynasty. This also reflects the historical changes of these two dynasties.
Therefore, Xi 'an is more appropriate and reasonable as the ancient capital of the 13th dynasty.