Imperial decline and collapse during the period of 600 BCE to 600 CE was caused by the inability to efficiently collect taxes in their empire, over-expansion, and a government’s inability to assert their power over a large group of people. One of the major causes of imperial decline and collapse was the inability for an empire to collect enough taxes. For example, the Mongol Empire. The Mongol Empire was known for their strong military pursuit for expansion, as their leader, Kublai Khan. But, the Mongol’s government could not collect enough taxes to pay for their massive army. This lead to the inability for them to reach their main goal, unite India, and resulted in their fall in the 6th Century. This was not good because they failed to maintain their goal. In the Roman Empire, taxes failed to be effective because of the Catholic church’s refusal to pay. Taxes were also so extreme, that the common person was not able to meet the given standards, and lead many individuals to starvation and bankruptcy. In extreme cases, if tax collectors could not collect the money from citizens, they could face a death sentence. This extreme taxing lead to many citizens of the Roman Empire to flee and find new homes with barbarians. The barbarians were the ones who caused the final fall of the Roman Empire years later. Which is ironic since many of the people of the Roman Empire had joined them.Another important factor of imperial decline and collapse was the over-expansion of empires. Although expansion might seem highly beneficial, it actually lead to the fall of many empire’s reign. This is because as an empire continued to gain more land, they eventually lost control of their fast-growing territory because it was difficult for them to maintain power in several different locations at once. Examples of this occurring during the period of 600 BCE to 600 CE include the Roman Empire and Chan China. During the period of expansion in the Roman Empire, Roman leaders extended their rule over areas as far as North Africa. Although the Roman Empire successfully conquered these areas, the ideologies and religions that were followed in these countries were resoundingly different than those of Christian ideologies. In Chan China, a close replica of the Rome Empire expansion occurred. It came to rule over groups of peoples who were not indigenously Chinese, which was the cause of a massive cultural wall. Lastly, an important factor was the fact that caused imperial decline and collapse was the government’s inability to control large groups of people. This ties to the previous reason of imperial decline, which was that over-expansion caused collapse in empires. When empires expanded their territories, areas of power moved farther and farther away from the central government. For example, the Han dynasty was incapable of asserting their power over their large amount of territory because of revolts by the common people against taxes. Therefore, the central government had to rely on local leaders to take care of individual areas, which lead these individuals to gain more power within their states. This lead to the ultimate decline of the Han because they were unable to control the now powerful leaders, and one powerful leader ended up overthrowing the Han emperor, which ended the Chan Dynasty. The reason why the government’s inability to control large populations ultimately caused their decline is because they had to deal with conflicts from the outside and within. There are many reasons why imperial decline and collapse occurred in 600 BCE to 600 CE, but a few of the most significant reasons are that some empires were unable to collect the necessary money from its population, over-expansion, and a government’s inability to assert their power over a large population.