The commercial policy that had led to the Navigation Act in October 1651 had made Cromwell want to attract the rich Jews of Amsterdam to London so that they might transfer their important trade interests with the Spanish Main from Holland to England.

The mission of Oliver St. John to Amsterdam, though failing to establish a coalition between English and Dutch commercial interests as an alternative to the Navigation Act, had negotiated with Menasseh Ben Israel and the Amsterdam community.

The mystically inclined Manasseh, a Marrano by birth and an outstanding man of letters, believes in a cabalistic Bible interpretation that Jews must dwell in every country before the Messiah can appear.

A pass had been granted to Menasseh to enter England, but he had been unable to use it because of the war between England and Holland from 1652 to 1654.

As soon as the war had ceased, Menasseh Ben Israel had sent his brother-in-law, David Abravanel Dormido, to London to present to the council a petition for the readmission of Jews.

The council, however, had refused to act.

Cromwell, heeding his Puritan advisors, who believe Jews should be allowed into England, confident they will convert to pure, Biblical Christianity, therefore induces Menasseh himself to come over to London, which he does at the end of September 1655, and here he prints his "humble address" to Cromwell.

A national conference, as a consequence of Manasseh’s plea to Cromwell, is in the early part of December summoned at Whitehall, which includes some of the kingdom's most eminent lawyers, divines, and merchants.

The lawyers declare no opposition to the Jews' residing in England, but both the divines and merchants are opposed to readmission, leading Cromwell to stop the discussion to prevent an adverse decision.

Antonio Fernandez Carvajal, besides advancing money to Parliament on cochineal, had been of service to Cromwell in obtaining information as to the Royalists' doings in Holland in 1656.

One of his servants, Somers, alias Butler, and also a relative, Alonzo di Fonseca Meza, have acted as intelligence sources for Cromwell in Holland, and have reported about Royalist levies, finances, and spies, and the relations between Charles II and Spain.

It is to Carvajal that Cromwell gives the assurance of the right of Jews to remain in England.

Under cover of this permission, Carvajal and Simon de Caceres purchase a piece of land for a Jewish cemetery in 1657, and Solomon Dormido, a nephew of Menasseh Ben Israel, is admitted to the Royal Exchange as a duly licensed broker of the City of London without taking the usual oaths involving faith in Christianity.

Carvajal had in August 1655 been allowed to take out letters of denization for himself and and his two sons.