The revelation, in 1644, that South American Indians prayed in Hebrew was astonishing.  The news was brought to the Jews of Amsterdam in September 1644 by a Portuguese Marrano trader from New Grenada.  He described a secret meeting with indigenous people in a remote location at a river in the mountains, at which the natives recited the first line of the Shema.  His conclusion was that the indigenous people there must be Jews.

The report was taken perfectly seriously. Menasseh ben Israel listened carefully and interrogated the trader at length, concluding that he was honest and truthful. But how was it possible? Some people were arguing that this showed that native Americans are descended from the lost tribes of Israel. After all, they must be biologically connected to the people of the Old World, and in some way travelled to America long ago.

A pamphlet was produced describing the report, and it was translated into English. Cromwell read it. He believed that the Second Coming depended on Jews being spread through all the countries of the world, and since they were evidently present in America it was his duty to bring them to England. That is how the process began which led to Jews moving to London from Amsterdam.

As it happens, Alan Ereira has spent the last 30 years working with an indigenous community in the mountains and jungles of what was New Granada. This community has remained virtually unchanged since the 17th century. By comparing his own knowledge of them with the report presented in Amsterdam, Alan Ereira believes he can offer a highly credible - and very surprising - explanation of the "Jewish Indians" - and new light on the settlement of Jews in England.