The diaspora was when the Jews moved out of Israel.
This meant that cultures were set up all over the world. Because of this different traditions emerged.
The destruction of the temple in Jerusalem meant animal sacrifices, the main way of communicating with God, became impossible. This led to prayers and acts of kindness being the main way of talking to God. It also meant priests had no role of authority.
As there was no way for the Jews to get to Jerusalem it meant a portable icon had to be made. Thus the Torah was born.
