Jewish religion got a foothold after the conquest of the land around Jerusalem.
Step-by-step explanation:
The Jews of the old had to travel far and wide in search of a land where they could live and had to turn from or flee from many great empires that were persecuting them for their religion.
This ended with the conquest of and settlement of the region of Jerusalem where the Jews finally found a home they could call their own and established their society there.
The land was to house Jews for the next 2 millennium and still continues to do so as it is called the holy land.