The Roman Empire and the Han Dynasty were some of the most powerful political entities in the history of the world. Both existing and ruling during the first century AD, the Han dynasty, and the Roman Empire, were extremely powerful with vast militaries and enormous quantities of resources. Even by today’s standards, these two empires would still be among the largest existent empires by landmass in they were recreated to match how they were at their respective heights. An interesting question to ask would be, how was it then that these apparently very powerful ancient empires crumbled and fell? The largest and most visible reasons for their collapses can be see in the decline in trade,excessive need for military spending due to nomadic tribes,and the failure of the political systems due to corruption or inability to act.One major cause of the collapse that was ongoing was the constant onslaught of Nomadic attackers. The Han Dynasty and the Roman empire both were pestered by tribes of Nomadic peoples. The Romans were harassed by Germanic tribes while the Han were harassed by the Huns. Germanic tribes had far more advanced military technology than the Huns and were quite a threat to Roman forces. During Caesar’s rule, nomadic peoples constantly attempted to conquer small cities and areas but, were almost always pushed away and had to settle on the outskirts of the Roman Empire. These attacks however called for a need of a large army from both empires due to the growing difficulty found in winning battles against the hordes of attackers that were coming from all angles. Partially due to this, taxes had to raised, “Virtually all the taxes and rents raised by the imperial government were spent on the military about 80% of the imperial budget in 150 AD.” (“The Imperial Economy,” in A Companion to the Roman Empire, Mattingly, )The Roman and Han empires both were very well set up in regards to infrastructure such as ports to circulate trade. However, decline in trade affected Rome far more than Han China. Most of the groups of people within Han China were somewhat self sufficient, and most of the trade that was conducted within Han China was carried out between these groups. The Roman economy however, “…was heavily reliant on trade and as thieves and bandits began stealing items a decline in trade and profits began to form” (‘Taxes And Trade in the Roman Empire 200 BC – AD 400’, Hopkins). Less trade reduced the amount of money that was going back into the government. In contrast to the decline in trade,the Roman and Han Empires raised taxes to support their growing armies trying to balance what was lost in this decline. As taxes increased however, the poor peasantry of both empires were more and more unable to pay them. Due to the fact that rich landowners in both Han China and the Roman Empire did not have to pay taxes, poor peasants flooded en masse to them for protection. In Rome, a vicious cycle began as trade began to be affected by the rising taxes, due to the fact that they generated inflation. “Such an increase in money supply might initially have stimulated commerce and production; but the increase in coins was too rapid not to have increased prices also. And in due course there was a downturn in trade” (‘Taxes And Trade in the Roman Empire 200 BC – AD 400’, Hopkins)Due to the rising taxes, which themselves were put in place due to a decline in trade and a need for heartier defenses against nomads, both empires experienced heavy civil and social unrest during their slow downfalls. Peasants in Han China became angered with the ever rising taxes and started to revolt. The revolts only grew in size and eventually the Han had to use their military to stop them but soon, needed more soldiers, which only increased taxes and recruitment. The Han government forced many peasants and farmers to fight, creating a larger divide and even more social unrest. While the Han had to deal with revolts due to excessive taxation the Romans had to suffer a rising religion. As Christianity spread, the Roman leaders became more and more upset that the message of the religion was catching on to the common peasants. The Roman leaders created laws against Christianity with severe punishments sometimes even being the possibility of death. Eventually, all plans to cease or slow the growth failed and Christianity continued to spread further breaking and shattering the once powerful empire like glass. “There are a number of reasons for the collapse of the Roman Empire — a decline that took place over many hundreds of years. The rise of Christianity did play a small, but not insignificant, part in the decline, in that it eroded traditional Roman beliefs and values and caused conflicts between Christians and those who continued to hold onto the old pagan philosophies. These conflicts led to persecution of the Christians, until the first Christian Emperor of Rome, Constantine, put a stop to the persecution.” (‘What caused the fall of the Roman Empire? Did Christianity play a role?’, Cliffsnotes.com)Eventually, as the weight of the Han and Roman Empires size exceeded their ability to maintain control over them, they collapse under the mountain of issues plaguing their enormous empires. There were many factors in the failings and subsequent collapse of once powerful empires. Something interesting to note is the sort of domino effect that seemed to be set in motion by the need for larger armies and a decline in trade. Both the Roman and Han empires had had long standing reigns however, minor mistakes made by the governments had over time grew and caused huge problems socially, economically and politically.The ultimate failure of these once great empires can be determined from the lack of power in the government as it diminished from the the central political system under the weight of impossibly difficult logistical situations that had to managed with empires of that size at that time. It simply became too difficult for even some of the best leaders to fix every single problem large and small that existed and eventually, some of the small problems that were neglected grew into enormous and catastrophic issues which would ultimately spell the end for both of these once great empires.