What led to the diaspora?

The last decisive event that led to the Jewish diaspora, had to do with the Roman inflicted genocide of Jews in 70 AD. This event still is one of the major reasons of conflict between Israel, Palestine and Arabic nations today.

Acording to the historian Josephus: "Josephus claims that 1,100,000 people were killed during the siege, of which a majority were Jewish, and that 97,000 were captured and enslaved, including Simon bar Giora and John of Giscala."[4]

Those who survived where taken captive and sent to Rome to serve as slaves.

Many fled to other Mediterranean countries; such as Egypt, Turkey, Spain, Syria Jordan, Morocco, etc.

After the genocide, the Romans introduced people from different surrounding nations, (mostly Arabic) and called it Palestine.

If you want further information about this go to Wikipedia under:

"Seige of Jerusalem (70)".