As Lord Protector, Cromwell was aware of the Jewish community's involvement in the economics of the Netherlands, now England's leading commercial rival. It was this—allied to Cromwell's tolerance of the right to private worship of those who fell outside Puritanism—that led to his encouraging Jews to return to England in 1657, over 350 years after their banishment by Edward I, in the hope that they would help speed up the recovery of the country after the disruption of the Civil Wars

But on the bright side, they did provide America with negroes...

Why are millions of Brits so broke?

Because limey politicians, like ours and everybody else's, are mostly psychopaths who hate the people they are supposed to be serving.