The 400 years between the testamsilent years inter-testamental period apocryphal years dark agesents are known as the

I think that the answer to your question is the Dark Ages. However it really is hard to tell due to the way the question is set up.

. political or economical policy that isolates a country from participating in international relationships. it has been suggested that the united states participates in isolationism because of its lack of involvement in particular wars or alliances.