How did the kingdom of Yelang, which claimed to be as prosperous as the Tang Dynasty, decline?

Yelang country is actually called Yelang country. It's really prosperous and has a vast territory. It is located in today's western Guizhou, covering Sichuan, Hunan, Guangxi and Yunnan. It cooperated with the Han Dynasty and once lent 100,000 soldiers to Emperor Wu of the Han Dynasty. In the end, Yelang did not obey the Han Dynasty. When fighting the enemies around him, the king was killed by Chen Li, an envoy of the Han Dynasty, and Yelang country soon went to extinction.

When it comes to "Yelang country", the first impression is mostly "Yelang arrogance", thinking that Yelang country is a small barbarian country and arrogantly calls itself a big country. In fact, Yelang Kingdom is a scapegoat. In BC 122, the special envoy of Emperor Wu of the Han Dynasty arrived in Yunnan, and the king of Yunnan asked him, "Who is bigger, Han or me?" Then the messenger met Yelang Wang, who asked him the same question. This is not arrogance, but inconvenient transportation in ancient times and backward information in small countries in remote areas.

At that time, Yelang was the most powerful country except Han Dynasty:

As far as territory is concerned, it has a vast territory. According to historical records, Yelang is the largest country in Southwest China, and now there are traces of its activities in Sichuan, Chongqing, Huguang and other places. It is indeed the largest country in Southwest China.

Economically, the ancient Maritime Silk Road entered foreign countries through Yelang country, and its own precious resources such as gold and silver made Yelang country extremely rich.

In terms of military strength, Yelang practiced Yelang system, uniting tribal forces such as priests, wizards, warriors and witches. Similar to the current "European Union", it is very strong in the southwest. Later, Emperor Wu of the Han Dynasty recovered the Fifth Route Army in Lingnan, including 100,000 elite troops from Yelang.

The performance of Yelang kingdom in territory, wealth and military strength is enough to witness its prosperity at that time, but it is still not as good as the Han Dynasty in the prosperous period. Finally, because of his arrogance and disobedience to the control of the Han dynasty, the leader was beheaded by the Han ambassador, and the Yelang kingdom was destroyed and disappeared into the long river of history.