The term: diaspora (in Ancient Greek, διασπορά – "a scattering or sowing of seeds") is used (without capitalization) to refer to any people or ethnic population who are forced or induced to...
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The first one was 585 to 515 BCE. the second is - 70 CE to the present day.
If you are talking about the current Jewish Diaspora, it began in the year 70 CE.
The Hebrew Diaspora means the entirety of the Jewish exile: the Jews in all the places of their dispersion.