The Catholic church was very much against interest in money lending, but it was too profitable for nobles and royalty to ignore.

So, nobles and royalty would deny Jews access to other employment and force them to become lenders [of noble/royal money].

Then, when things went to shit, the noble or royal in question would blame their Jew(s).

So:
1. Yes, the lenders of old were largely Jewish.
2. No, they never had any real power.

This doesn't happen anymore, but the average Jew isn't any different from the average anything really.

Isn't history wonderful?
Isn't reality bland?