How did judaism survive over time as a religion?

The Romans expelled all Jews from Israel in the First Century, but the religion has survived the persecution over the years. The primary reason for the survival of the faith of Judaism is the sense of community that Jews have with one another.Jews followed a strict code of dietary and moral laws to develop this unity.

where is thing if you show me on the map or have a map i can answer your question

the answer would more than likely a.)falling crop prices  

hope the answer is right and ,either way have a nice day.