The Talmud (Sanhedrin 39b) says that we are required to learn from the behavior of all decent, civilized people.
So, for example, when we become aware that Muslims, on religious principle, never complain about the weather, we must make that principle ours as well. When we become aware that Christians honor their churches by dressing in their finest and behaving with decorum, we must be sure to behave (at least) in a similar degree of respect in synagogue.
Et cetera.
It is unclear what this question is asking. Some possible interpretations include, but are not limited to: What can a person learn about the Jewish Diaspora? What is there to know? What can Jews learn from the experience of the Diaspora? What can Jews learn from non-Jews in the Diaspora? What can a person apply from Jewish Diaspora to examine similar cases and problems? Please see the Related Questions below. At the time that this answer is written only the first one has been answered, but hopefully others will contribute the remaining answers.
Passover is usually only celebrated by Jews
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They were (and are) known as "Diaspora Jews."
Diaspora
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If you are referring to the Jewish Diaspora, then it was the Jews that experienced it.
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The diaspora, or the exile (galut). See also:More on this topic
Exiles; Diaspora JewsSee also:More about the diaspora
The Exile of Jews from palestine is known as the Diaspora
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