"The Roman Empire of the fourth century A.D. had existed as an important power for over 1000 years. The Romans brought stability, prosperity, and order to the civilized West. Well maintained roads connected the far reaches of the empire with the capital at Rome. These were built originally for military purposes, but improved all communication and trade. Roman law kept the internal peace and 20 to 30 Roman legions defended the frontiers." But this civilization could not last forever.
There are many reasons for the fall of the Roman Empire: poor leadership, military spending, civilization brought on by the introduction and establishment of Christianity, political corruption and invasion. In 284 A.D., Diocletian came to the throne after much political disorganization and internal dissent. He decided to divide the Empire because it was too large to be ruled by one person. He controlled the eastern half and his colleague, Maximian controlled the western half.
Diocletian also created officials called Caesars to help manage the administration and to take over the empire in case the Emperors were to die. This made it so the empire would never go without a ruler and it would prevent one ruler from ceasing the whole empire.
In 305, Diocletian retired and forced Maximian to do the same. The rule passed to the two Caesars. In 324, one of the Caesar's sons, Constantine, became the single ruler over a unified empire. He became the first Christian ruler and in 325 developed for the Roman Empire the basic belief for Orthodox Christianity - the Nicene Creed.
In 379, the emperor Theodosius declared Christianity the state religion of Rome, and made all pagan religions illegal; thus, the establishment of Christianity. Some historians believe that Christianity made many Roman citizens into pacifists, making it more difficult to defend against barbarian attackers. Also money spent on churches and religious icons could have been used to better maintain the empire.
Another reason for the decline of the Roman Empire, military spending, left few resources for vital activities such as providing public housing and maintaining quality roads and aqueducts. Maintaining an army to defend the border of the Empire from barbarian attacks was a constant drain on the government. "Frustrated Romans lost their desire to defend the Empire." The emperors had to begin hiring soldiers recruited from the unemployed city mobs, which proved to be both unreliable and expensive. They were forced to raise taxes often, which in turn led to increased inflation.
In 410, a Germanic tribe, the Visigoths, moved in to Rome to stay out of the way of the Huns. While in Rome, they took over and destroyed parts of the city. In 453, Attila and the Huns began to attack and take land from the Romans. In 455, the Vandals, another Germanic tribe, conquered Rome. In 476 A.D. the Germanic general Ocacer overthrew the last of the Roman Emperors, Augustulus Romulus.
From then on the empire was ruled by the Germanic chieftain. Roads and bridges were left in disrepair and fields left untilled. Pirates and bandits made travel unsafe. Cities could not be maintained without goods from the farms. Trade and business began to disappear and. thus, the decline of the Roman Empire.