The Dark Ages describe a period of time after the fall of Rome in 476. There is some debate as to how long the period lasted, but many agree it was until 900 or 1000. There are several characteristics of the Dark Ages. One characteristic was the lack of forward thinking ideas and practices that existed during this time. There was a lack of Latin literature and other cultural developments during the Dark Ages. Another characteristic of this time was religious struggle. Orthodox Christians and Catholics looked at this time period very differently. Orthodox Christians felt it was a corrupt period, and they rejected many ways of the Catholic Church. Catholics, however, did not see things the same way. They felt it was a productive era. This era was also known for Muslim conquests. Some of the issues between Catholics and Muslims can be traced back to this time period. While there was religious conflict, the Dark Ages are viewed as an era of faith. People, in some way, sought out a divine power. Finally, the feudal system developed during this time. This developed mainly because there was no strong central power during this time period. The feudal system, with its castles and walled towns, provided protection from invasion by the barbarians.