Explain why eastern churches were known as the Orthodox Church

The Orthodox Catholic Church is commonly known as the Eastern Orthodox Church, partly to avoid confusion with the Roman Catholic Church. It counts around 200 million members, most of them in eastern Europe, Greece and the Caucasus. Its traditional base is in modern-day Istanbul, previously known as Constantinople.

answer; taking up arms to defend the nation;

1. it was caused by feudalism

2. charlemagne used christianity as a major cornerstone for his rule. cloisters were built all over the empire to act as centers for the (re)population of the vast european wilderness.

3. the europeans feared the next raid every time chetak

i'm not so sure about #6. but i hope i you with the first 3.