Although the Zhou Dynasty implemented a system of sub-feudalism, there were many princely states everywhere, but only Zhou Tianzi was the lord of the world! It is reasonable to say that Tianzi is rich in all corners of the world and should be the richest person in the world, but the last Tianzi king of the Zhou Dynasty, King Zhou Zhao, has become a laughingstock. King Zhou Zhao reigned for a long time, for fifty-nine years, but he was in debt to the people, and in order to avoid debt collection, he actually fled to the high platform in the palace, leaving behind the story of "high debt". So, why is Tangtang Zhou Tianzi so poor?
In fact, as early as the zhou ping king, the ancestor of the zhou zhao king, the zhou dynasty's finances were already in trouble. In 720 BC, King Ping of Zhou fell ill and died, and during the funeral, the Zhou royal family actually had no money, and the reigning King Huan of Zhou had to send someone to the state of Lu to beg for money and goods to handle the funeral of Zhou Tianzi. King Ping of Zhou was the first son of the Eastern Zhou Dynasty, and King Zhao of Zhou was the last, a difference of four or five hundred years, which shows that the poverty of the Zhou royal family has a long history.

First, no one gives money
After king Wu of Zhou destroyed the Shang Dynasty, he divided the sons of the royal family, heroes, and descendants of the previous kings, and gave them a large area of land and population. However, Zhou Tianzi is still a king, the princely states are still subjects, and they are still in a relationship between kings and subjects, and these princely states must respect the orders of Zhou Tianzi, regularly visit the Heavenly Son, and at the same time pay tribute to Zhou Tianzi. These tributes from the princely states were an important source of income for the Zhou royal family.
However, after King Ping of Zhou moved east to Luoyi, due to problems with the way he ascended the throne, he was not recognized by most of the princely states for a long time. At the same time, King Ping of Zhou also exchanged hostages with Zheng Zhuanggong, which caused zhou tianzi's authority to plummet, and those princely states looked down on zhou tianzi even more. Therefore, during the Eastern Zhou Dynasty, almost no princely states paid tribute to Zhou Tianzi. This shows that the Zhou Dynasty's sub-feudal system completely collapsed, and at the same time, Zhou Tianzi's prestige was swept away.
Second, I don't have any money
During the Western Zhou Dynasty, the territory directly under the jurisdiction of the Zhou royal family was very large, and the population in the territory was large, so naturally it was rich and powerful. However, when the Western Zhou Dynasty fell, Inuyasha entered the capital and burned and looted, looting the wealth accumulated by the Western Zhou For hundreds of years. Due to the constant war in the Guanzhong region, King Ping of Zhou was forced to abandon Hojing and move the capital to Luoyi. At this point, the territory directly under the Zhou royal family was reduced by more than half, and only six hundred miles of territory remained.
Due to the sharp decline in land and population, and the number of nobles in the Zhou Dynasty was still very large, in this case, there was a situation of "more monks and less porridge", which led to the financial difficulties of the Zhou Dynasty. With the development of agriculture, the well field system on which the Zhou Dynasty relied on it disintegrated, the land was transformed from state-owned to private, and in the early Warring States period, the well field system completely collapsed, which further aggravated the financial difficulties of the Zhou royal family. At the same time, the Zhou royal family also split into the Eastern Zhou Kingdom and the Western Zhou Kingdom, and the power was more dispersed.
Third, someone asks for money
In the early Spring and Autumn Period, the direct territory of the Zhou royal family was still not small, but due to the sweeping prestige of Tianzi, it was constantly eroded by the surrounding princely states, and during this period, the Zheng state and the Jin state encroached on many Zhou Tianzi's territories. In the Warring States period, the seven males stood side by side, and no one paid attention to Zhou Tianzi. Countries carried out various extortions against the Zhou royal family, and even South Korea demanded money and grain from the royal family, which made the already difficult royal family's finances worse.
During the reign of King Zhao of Zhou, he borrowed a lot of money from people and cobbled together a force, intending to follow the Chu state in its crusade against the Qin state. As a result, the allied armies of various countries were defeated, and the King of Zhou zhao was collected by the creditors and forced to build a high debt. In 256 BC, the Qin army attacked the Western Zhou kingdom where King Zhao of Zhou was located, and the Western Zhou Jun was forced to plead guilty and "sacrifice thirty-six of his yi and thirty thousand mouths.". In the same year, King Zhao of Zhou fell ill and died, and the Zhou Dynasty ceased to exist.
References: 1. "History"; 2. "History of the Warring States"